### Tournament Brackets

For the three first Selective Science Fights, the Tournament Bracket established at the Opening Ceremony by drawing lots determines what Team competes in what Group and the sequence of performances in each Group. In contrast, the Brackets for Science Fight 4 and onwards depend on the Team Rank after the last completed Science Fight and no longer determine the sequence of performances within a Group, which is decided by winner of Captain's Contest.

The Tournament Bracket is established according to an exact procedure made public by the GC during the Opening Ceremony.

Building such a Bracket is an interesting combinatorial optimization puzzle similar to the *Social Golfer Problem* or *Kirkman's Schoolgirl Problem* with many additional constraints.

The exact structure of an IYNT Bracket aims at such a distribution of Teams among the Groups that the following requirements and restrictions are respected, in order of decreasing priority:

**The number of parallel competition Groups is brought to an absolute minimum.**It therefore equals*N*/3, rounded up to the next whole number, where*N*is the total number of Teams in the IYNT. Consequently, there can be no more than 2 two-Team Groups during any Science Fight.**No two Teams meet more than once**prior to the Selective Science Fight 4. It is possible to fully satisfy this condition for*N*≥7 and*N*=4. Ensuring the minimum number and the most uniform distribution of repeated pairings per any two Teams is an absolute requirement for*N*=5 and*N*=6 when Teams are arranged such that no two of them meet more than twice.**Each Team plays as few two-Team Science Fights as possible**prior to the Selective Science Fight 4. For*N*≥16, each Team plays no more than one two-Team Science Fight. For*N*≥5, each Team plays no more than two two-Team Science Fights. In each such instance, the number of two-Team Science Fights per Team is distributed in the most even manner.- By passing from one Science Fight to next Science Fight,
**each Team switches their Role**in Stage I in the standard order (Reporter-Reviewer-Opponent.) This condition is fully satisfied for any*N*≥2. - As to ensure that
**no two Teams from one country meet**prior to the Selective Science Fight 4, they would draw lots from a sufficiently large pool such that any pairing within the pool is impossible. This procedure is similar to*seeding*and requires pools no smaller than the number of Teams from one country. Such pools, of different size, exist for any*N*≥5. For convenience, the largest pools have the size of*N*/3 (rounded up) and are arranged such that all Teams playing a particular Role in Stage I of Science Fight 1 do not meet each other in any Science Fight. **No Team competes in any Group more than once.**This condition is enforced only when all higher-level priorities are achieved. It is then possible to fully satisfy the condition for*N*≥19. Ensuring the minimum number of and the most even distribution of returns to a Group is a lower-level priority for*N*<19. For*N*≥5, no Team plays in one Group more than twice.

Below are given the optimized standard Tournament Brackets of up to *N*=36 Teams, where the numbers indicate the lot and rows each Science Fight.

### 34...36 Teams: 12 Groups

Group A | Group B | Group C | Group D | Group E | Group F | Group G | Group H | Group I | Group J | Group K | Group L |
---|---|---|---|---|---|---|---|---|---|---|---|

1 13 25 | 2 14 26 | 3 15 27 | 4 16 28 | 5 17 29 | 6 18 30 | 7 19 31 | 8 20 32 | 9 21 33 | 10 22 34 | 11 23 35 | 12 24 36 |

16 26 12 | 17 27 1 | 18 28 2 | 19 29 3 | 20 30 4 | 21 31 5 | 22 32 6 | 23 33 7 | 24 34 8 | 13 35 9 | 14 36 10 | 15 25 11 |

27 11 19 | 28 12 20 | 29 1 21 | 30 2 22 | 31 3 23 | 32 4 24 | 33 5 13 | 34 6 14 | 35 7 15 | 36 8 16 | 25 9 17 | 26 10 18 |

Each Team meets 6 other competitors, each of them exactly once.

In case of thirty-five Teams, Team 36 is omitted, and Teams 8, 10, 12, 14, 16, 24 land once in a two-Team Group (thus meeting 5 other competitors.) In case of thirty-four Teams, Teams 35 and 36 are omitted, and Teams 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 23, 24 land once in a two-Team Group (thus meeting 5 other competitors.)

Each Team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Each Team plays only once in one Group.

These pools of Teams never meet in whatever mutual pairing: 1+2+3+4+5+6+7+8+9+10+11+12 (Reporters in Stage I, SF 1), 13+14+15+16+17+18+19+20+21+22+23+24 (Opponents in Stage I, SF 1), 25+26+27+28+29+30+31+32+33+34+35+36 (Reviewers in Stage I, SF 1), and 36 tensome pools of other combinations.

### 31...33 Teams: 11 Groups

Group A | Group B | Group C | Group D | Group E | Group F | Group G | Group H | Group I | Group J | Group K |
---|---|---|---|---|---|---|---|---|---|---|

1 12 23 | 2 13 24 | 3 14 25 | 4 15 26 | 5 16 27 | 6 17 28 | 7 18 29 | 8 19 30 | 9 20 31 | 10 21 32 | 11 22 33 |

21 27 11 | 22 28 1 | 12 29 2 | 13 30 3 | 14 31 4 | 15 32 5 | 16 33 6 | 17 23 7 | 18 24 8 | 19 25 9 | 20 26 10 |

28 10 19 | 29 11 20 | 30 1 21 | 31 2 22 | 32 3 12 | 33 4 13 | 23 5 14 | 24 6 15 | 25 7 16 | 26 8 17 | 27 9 18 |

Each Team meets 6 other competitors, each of them exactly once.

In case of thirty-two Teams, Team 33 is omitted, and Teams 4, 6, 11, 13, 16, 22 land once in a two-Team Group (thus meeting 5 other competitors.) In case of thirty-one Teams, Teams 32 and 33 are omitted, and Teams 3, 4, 5, 6, 10, 11, 12, 13, 15, 16, 21, 22 land once in a two-Team Group (thus meeting 5 other competitors.)

Each Team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Each Team plays only once in one Group.

These pools of Teams never meet in whatever mutual pairing: 1+2+3+4+5+6+7+8+9+10+11 (Reporters in Stage I, SF 1), 12+13+14+15+16+17+18+19+20+21+22 (Opponents in Stage I, SF 1), 23+24+25+26+27+28+29+30+31+32+33 (Reviewers in Stage I, SF 1), and 33 ninesome pools of other combinations.

### 28...30 Teams: 10 Groups

Group A | Group B | Group C | Group D | Group E | Group F | Group G | Group H | Group I | Group J |
---|---|---|---|---|---|---|---|---|---|

1 11 21 | 2 12 22 | 3 13 23 | 4 14 24 | 5 15 25 | 6 16 26 | 7 17 27 | 8 18 28 | 9 19 29 | 10 20 30 |

12 30 8 | 13 21 9 | 14 22 10 | 15 23 1 | 16 24 2 | 17 25 3 | 18 26 4 | 19 27 5 | 20 28 6 | 11 29 7 |

28 3 16 | 29 4 17 | 30 5 18 | 21 6 19 | 22 7 20 | 23 8 11 | 24 9 12 | 25 10 13 | 26 1 14 | 27 2 15 |

Each Team meets 6 other competitors, each of them exactly once.

In case of twenty-nine Teams, Team 30 is omitted, and Teams 5, 8, 10, 12, 18, 20 land once in a two-Team Group (thus meeting 5 other competitors.) In case of twenty-eight Teams, Teams 29 and 30 are omitted, and Teams 4, 5, 7, 8, 9, 10, 11, 12, 17, 18, 19, 20 land once in a two-Team Group (thus meeting 5 other competitors.)

Each Team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Each Team plays only once in one Group.

These pools of Teams never meet in whatever mutual pairing: 1+2+3+4+5+6+7+8+9+10 (Reporters in Stage I, SF 1), 11+12+13+14+15+16+17+18+19+20 (Opponents in Stage I, SF 1), 21+22+23+24+25+26+27+28+29+30 (Reviewers in Stage I, SF 1), and 30 eightsome pools of other combinations.

### 25...27 Teams: 9 Groups

Group A | Group B | Group C | Group D | Group E | Group F | Group G | Group H | Group I |
---|---|---|---|---|---|---|---|---|

1 10 19 | 2 11 20 | 3 12 21 | 4 13 22 | 5 14 23 | 6 15 24 | 7 16 25 | 8 17 26 | 9 18 27 |

11 27 7 | 12 19 8 | 13 20 9 | 14 21 1 | 15 22 2 | 16 23 3 | 17 24 4 | 18 25 5 | 10 26 6 |

26 2 12 | 27 3 13 | 19 4 14 | 20 5 15 | 21 6 16 | 22 7 17 | 23 8 18 | 24 9 10 | 25 1 11 |

Each Team meets 6 other competitors, each of them exactly once.

In case of twenty-six Teams, Team 27 is omitted, and Teams 3, 7, 9, 11, 13, 18 land once in a two-Team Group (thus meeting 5 other competitors.) In case of twenty-five Teams, Teams 26 and 27 are omitted, and Teams 2, 3, 6, 7, 8, 9, 10, 11, 12, 13, 17, 18 land once in a two-Team Group (thus meeting 5 other competitors.)

Each Team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Each Team plays only once in one Group.

These pools of Teams never meet in whatever mutual pairing: 1+2+3+4+5+6+7+8+9 (Reporters in Stage I, SF 1), 10+11+12+13+14+15+16+17+18 (Opponents in Stage I, SF 1), 19+20+21+22+23+24+25+26+27 (Reviewers in Stage I, SF 1), and 27 sevensome pools of other combinations.

### 22...24 Teams: 8 Groups

Group A | Group B | Group C | Group D | Group E | Group F | Group G | Group H |
---|---|---|---|---|---|---|---|

1 9 17 | 2 10 18 | 3 11 19 | 4 12 20 | 5 13 21 | 6 14 22 | 7 15 23 | 8 16 24 |

10 24 6 | 11 17 7 | 12 18 8 | 13 19 1 | 14 20 2 | 15 21 3 | 16 22 4 | 9 23 5 |

23 2 11 | 24 3 12 | 17 4 13 | 18 5 14 | 19 6 15 | 20 7 16 | 21 8 9 | 22 1 10 |

Each Team meets 6 other competitors, each of them exactly once.

In case of twenty-three Teams, Team 24 is omitted, and Teams 3, 6, 8, 10, 12, 16 land once in a two-Team Group (thus meeting 5 other competitors.) In case of twenty-two Teams, Teams 23 and 24 are omitted, and Teams 2, 3, 5, 6, 7, 8, 9, 10, 11, 12, 15, 16 land once in a two-Team Group (thus meeting 5 other competitors.)

Each Team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Each Team plays only once in one Group.

These pools of Teams never meet in whatever mutual pairing: 1+2+3+4+5+6+7+8 (Reporters in Stage I, SF 1), 9+10+11+12+13+14+15+16 (Opponents in Stage I, SF 1), 17+18+19+20+21+22+23+24 (Reviewers in Stage I, SF 1), and 24 sixsome pools of other combinations.

### 19...21 Teams: 7 Groups

Group A | Group B | Group C | Group D | Group E | Group F | Group G |
---|---|---|---|---|---|---|

1 8 15 | 2 9 16 | 3 10 17 | 4 11 18 | 5 12 19 | 6 13 20 | 7 14 21 |

9 21 5 | 10 15 6 | 11 16 7 | 12 17 1 | 13 18 2 | 14 19 3 | 8 20 4 |

20 2 10 | 21 3 11 | 15 4 12 | 16 5 13 | 17 6 14 | 18 7 8 | 19 1 9 |

Each Team meets 6 other competitors, each of them exactly once.

In case of twenty Teams, Team 21 is omitted, and Teams 3, 5, 7, 9, 11, 14 land once in a two-Team Group (thus meeting 5 other competitors.) In case of nineteen Teams, Teams 20 and 21 are omitted, and Teams 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14 land once in a two-Team Group (thus meeting 5 other competitors.)

Each Team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Each Team plays only once in one Group.

These pools of Teams never meet in whatever mutual pairing: 1+2+3+4+5+6+7 (Reporters in Stage I, SF 1), 8+9+10+11+12+13+14 (Opponents in Stage I, SF 1), 15+16+17+18+19+20+21 (Reviewers in Stage I, SF 1), 1+10+11+13+14, 1+16+18+20+21, 2+8+11+12+14, 2+15+17+19+21, 3+8+9+12+13, 3+15+16+18+20, 4+9+10+13+14, 4+16+17+19+21, 5+8+10+11+14, 5+15+17+18+20, 6+8+9+11+12, 6+16+18+19+21, 7+9+10+12+13, 7+15+17+19+20, 8+16+17+19+21, 9+15+17+18+20, 10+16+18+19+21, 11+15+17+19+20, 12+16+18+20+21, 13+15+17+19+21, 14+15+16+18+20 (21 fivesome pools.)

### 16...18 Teams: 6 Groups

Group A | Group B | Group C | Group D | Group E | Group F |
---|---|---|---|---|---|

1 7 13 | 2 8 14 | 3 9 15 | 4 10 16 | 5 11 17 | 6 12 18 |

8 18 4 | 9 13 5 | 10 14 6 | 11 15 1 | 12 16 2 | 7 17 3 |

13 3 11 | 14 4 12 | 15 5 7 | 16 6 8 | 17 1 9 | 18 2 10 |

Each Team meets 6 other competitors, each of them exactly once.

In case of seventeen Teams, Team 18 is omitted, and Teams 2, 4, 6, 8, 10, 12 land once in a two-Team Group (thus meeting 5 other competitors.) In case of sixteen Teams, Teams 17 and 18 are omitted, and Teams 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 land once in a two-Team Group (thus meeting 5 other competitors.)

Each team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Teams 13, 14, 15, 16, 17, 18 play twice in one Group, all other Teams play only once in one Group.

These pools of Teams never meet in whatever mutual pairing: 1+2+3+4+5+6 (Reporters in Stage I, SF 1), 7+8+9+10+11+12 (Opponents in Stage I, SF 1), 13+14+15+16+17+18 (Reviewers in Stage I, SF 1), 1+8+10+12, 1+14+16+18, 2+7+9+11, 2+13+15+17, 3+8+10+12, 3+14+16+18, 4+7+9+11, 4+13+15+17, 5+8+10+12, 5+14+16+18, 6+7+9+11, 6+13+15+17, 7+14+16+18, 8+13+15+17, 9+14+16+18, 10+13+15+17, 11+14+16+18, 12+13+15+17 (18 foursome pools.)

### 13...15 Teams: 5 Groups

Group A | Group B | Group C | Group D | Group E |
---|---|---|---|---|

1 6 11 | 2 7 12 | 3 8 13 | 4 9 14 | 5 10 15 |

8 15 2 | 9 11 3 | 10 12 4 | 6 13 5 | 7 14 1 |

11 4 7 | 12 5 8 | 13 1 9 | 14 2 10 | 15 3 6 |

Each Team meets 6 other competitors, each of them exactly once.

In case of fourteen Teams, Team 15 is omitted, and Teams 2, 3, 5, 6, 8, 10 land once in a two-Team Group (thus meeting 5 other competitors.) In case of thirteen Teams, Teams 14 and 15 are omitted, Teams 2, 10 land in a two-Team Group twice (thus meeting 4 other competitors), Teams 1, 3, 4, 5, 6, 7, 8, 9 land in a two-Team Group once (thus meeting 5 other competitors), and remaining Teams 11, 12, 13 always land in three-Team Groups.

Each team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Teams 11, 12, 13, 14, 15 play twice in one Group, all other Teams play only once in one Group.

These pools of Teams never meet in whatever mutual pairing: 1+2+3+4+5 (Reporters in Stage I, SF 1), 6+7+8+9+10 (Opponents in Stage I, SF 1), 11+12+13+14+15 (Reviewers in Stage I, SF 1), 1+8+10, 1+12+15, 2+6+9, 2+11+13, 3+7+10, 3+12+14, 4+6+8, 4+13+15, 5+7+9, 5+11+14, 6+12+14, 7+13+15, 8+11+14, 9+12+15, 10+11+13 (15 threesome pools.)

### 10...12 Teams: 4 Groups

Group A | Group B | Group C | Group D |
---|---|---|---|

1 5 9 | 2 6 10 | 3 7 11 | 4 8 12 |

8 10 3 | 5 11 4 | 6 12 1 | 7 9 2 |

10 4 7 | 11 1 8 | 12 2 5 | 9 3 6 |

Each Team meets 6 other competitors, each of them exactly once.

In case of eleven Teams, Team 12 is omitted, and Teams 1, 2, 4, 5, 6, 8 land once in a two-Team Group (thus meeting 5 other competitors.) In case of ten Teams, Teams 11 and 12 are omitted, Teams 1, 4, 5, 8 land in two-Team Groups twice (thus meeting 4 other competitors), Teams 2, 3, 6, 7 land in a two-Team Group once (thus meeting 5 other competitors), and remaining Team 10 always lands in three-Team Groups.

Each Team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Teams 9, 10, 11, 12 play twice in one Group, all other Teams play only once in one Group.

These pools of Teams never meet in whatever mutual pairing: 1+2+3+4 (Reporters in Stage I, SF 1), 5+6+7+8 (Opponents in Stage I, SF 1), 9+10+11+12 (Reviewers in Stage I, SF 1), 1+7, 1+10, 2+8, 2+11, 3+5, 3+12, 4+6, 4+9, 5+10, 6+11, 7+12, 8+9 (12 pairs.)

### 7...9 Teams: 3 Groups

Group A | Group B | Group C |
---|---|---|

1 4 7 | 2 5 8 | 3 6 9 |

4 8 3 | 5 9 1 | 6 7 2 |

7 3 5 | 8 1 6 | 9 2 4 |

Each Team meets 6 other competitors, each of them exactly once.

In case of eight Teams, Team 9 is omitted, Teams 1, 2, 3, 4, 5, 6 land once in a two-Team Group (thus meeting 5 other competitors), and remaining Teams 7, 8 always land in three-Team Groups. In case of seven Teams, Teams 8 and 9 are omitted, Teams 1, 2, 3, 4, 5, 6 land twice in two-Team Groups (thus meeting 4 other competitors), and remaining Team 7 always lands in three-Team Groups.

Each Team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Each Team plays in one Group exactly twice.

These pools of Teams never meet in whatever mutual pairing: 1+2+3 (Reporters in Stage I, SF 1), 4+5+6 (Opponents in Stage I, SF 1),
7+8+9 (Reviewers in Stage I, SF 1).

### 5...6 Teams: 2 Groups

Group A | Group B |
---|---|

1 3 5 | 2 4 6 |

3 6 2 | 4 5 1 |

6 1 4 | 5 2 3 |

Each Team meets 4 other competitors, two of them once and two of them twice.

In case of five Teams, Team 6 is omitted, Teams 2, 4 land in two-Team Groups twice, Teams 1, 3 land in a two-Team Group once, and remaining Team 5 always lands in three-Team Groups. Teams 1, 2, 3, 4 then meet 3 other competitors, and Team 5 meets 4 other competitors.

Each Team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Each team Plays in one Group exactly twice.

These pairs of Teams never meet: 1+2 (Reporters in Stage I, SF 1), 3+4 (Opponents in Stage I, SF 1), 5+6 (Reviewers in Stage I, SF 1). These pairs or Teams meet once: 1+3, 1+6, 2+4, 2+5, 3+6, 4+5. These pairs of Teams meet twice: 1+4, 1+5, 2+3, 2+6, 3+5, 4+6.

### 4 Teams: 2 Groups

Group A | Group B |
---|---|

1 3 | 2 4 |

3 4 | 2 1 |

4 1 | 3 2 |

Each Team meets all 3 other competitors, each of them exactly once.

Each Team assumes each of two Roles in Stage I of Science Fights, changing them only once from Reporter to Reviewer-Opponent.

Teams 1, 3, 4 play in one Group twice, and remaining Team 2 plays in one Group three times.

### 2...3 Teams: 1 Group

Group A |
---|

1 2 3 |

2 3 1 |

3 1 2 |

Each Team meets all 2 other competitors, each of them exactly three times.

In case of two Teams, Team 3 is omitted, and Teams 1, 2 land in a two-Team Group three times.

Each Team assumes each of three Roles in Stage I of every Science Fight, changing them from Reporter, to Reviewer, and to Opponent.

Each Team plays in one group three times.

### Brackets used at past IYNTs

Below are given the Brackets of actual past IYNTs that reflect the structure and outcomes of each Tournament.

#### 16 Teams (1st IYNT 2013)

SF | Group A | Group B | Group C | Group D | Group E | Group F |
---|---|---|---|---|---|---|

SF 1 | [1 7 13] | [2 8 14] | [3 9 15] | [4 10 16] | [5 11 | [6 12 |

SF 2 | [12 | [7 | [8 13 6] | [9 14 1] | [10 15 2] | [11 16 3] |

SF 3 | [15 6 11] | [16 1 12] | [ | [ | [13 4 9] | [14 5 10] |

SF 4 | [2-9- [2 9 | [3-10-13] [10 3 13] | [4-11-14] [11 4 14] | [5-12-15] [5 12 15] | [6-7-16] [7 6 16] | [1-8- [1 8 |

sF | [r1-r6-r7] [12 2 9] | [r2-r5-r8] [7 6 3] | [r3-r4-r9-rg] [5 1 4 10] | --- | --- | --- |

Fin | [vA-vB-vC-vt] [10 11 7 3] | --- | --- | --- | --- | --- |

As to ensure that any two Teams from one country never meet until Semi-Finals, two Teams of Bulgaria, three Teams of Russia, and Team of Moldova drew lots from the pool 1+2+3+4+5+6. Next, three Teams of Turkey, and Teams of Afghanistan, Belarus, and Georgia drew lots from the pool 7+8+9+10+11+12. The rest drew lots from the pool 13+14+15+16. The bracket was fixed in the Regulations. Despite restrictions of the competition building to accommodate all three-Team Groups, the bracket was not amended, but the Group labels were switched on the doors for two-Team Groups.

#### 5 Teams (2nd IYNT 2014)

Science Fight | A | B |
---|---|---|

Science Fight 1 | [1 3 | [2 6 4] |

Science Fight 2 | [4 6 1] | [ |

Science Fight 3 | [ | [6 2 3] |

Science Fight 4 | [1 6 3] | [2 |

Finals | [r1-r2-r3] [4 6 2] | --- |

As to ensure that two Teams of Bulgaria never meet before Finals, they drew lots from the pool 1+2. The rest drew lots from the pool 3+4+5+6, because a sixth Team was expected to arrive just after the Opening Ceremony, but never appeared.

#### 10 Teams (3rd IYNT 2015)

SF | Group A | Group B | Group C | Group D |
---|---|---|---|---|

SF 1 | [1 3 7] | [4 8 x] | [2 5 9] | [6 10 x] |

SF 2 | [9 6 x] | [10 3 2] | [7 4 x] | [8 5 1] |

SF 3 | [5 10 x] | [6 2 7] | [3 8 x] | [4 1 9] |

SF 4 | [R1+R8+R9] [6 3 4] | [R3+R6+x] [2 5 x] | [R2+R7+R10] [8 7 1] | [R4+R5+x] [9 10 x] |

sF | [R5+R4+R1] [3 10 5] | [R6+R3+R2] [8 7 9] | --- | --- |

Fin | [vA+vB+v1] [9 5 3] | --- | --- | --- |

The bracket was custom-designed for the IYNT 2015. Countries represented by one Team drew lots from the pool 3+4+5+6+7+8+9+10 (Belarus-Spectrum pulled 10, China 3, Bulgaria 6, Croatia 5, and Georgia-Georgians 9), thus leaving lots 4, 7, 8 in the pool. As to ensure that three Teams from Russia never meet until Semi-Finals, Russia-MG 12 and Russia-Voronezh-1 drew lots from the pool 1+2, and then Russia-Voronezh-2 drew lots from an intersection of sets 4+6+8+10 and 4+7+8 (lots remaining from the first pool; Russia-MG 12 pulled 1, Russia-Voronezh-1 pulled 2), eventually drawing 4 (from a choice of 4 and 8.) Serbia-1 and Serbia-2 were then left with choices also not meeting until Semi-Finals (7 and 8), and pulled 8 (Serbia-1) and 7 (Serbia-2).

#### 16 Teams (4th IYNT 2016)

SF | Group A | Group B | Group C | Group D | Group E | Group F |
---|---|---|---|---|---|---|

1 | [1 7 13] | [2 8 14] | [3 9 15] | [4 10 16] | [5 11 | [6 12 |

2 | [9 16 6] | [12 13 3] | [7 14 4] | [8 15 5] | [10 | [11 |

3 | ||||||

3 | [r1 r6 r7] [1 13 6] | [r2 r5 r8] [5 9 8] | [r3 r4 r9] [3 12 15] | --- | --- | --- |

4 | [r1+r12+r13] [15 8 1] | [r2+r11+r14] [14 5 7] | [r3+r10+r15] [10 11 3] | [r4+r9+r16] [13 4 16] | [r5+r8+ [9 12 | [r6+r7+ [6 2 |

sF | [r1+r6+r7] [5 4 12] | [r2+r5+r8] [2 1 9] | [r3+r4+r9] [6 3 10] | --- | --- | --- |

Fin | [vA+vB+vC] [3 5 1] | --- | --- | --- | --- | --- |

A bracket for 18 Teams provided in previous Regulations v. 2015/02/25 was amended for SF 2, SF 3, and SF 4 such that two-Team groups would always land in E and F, due to restrictions of the competition building. The initial bracket for SF 3 was not executed as only 9 Teams were allowed. Countries represented by one Team drew lots from the pool 1+2+3+4+5+6 (Belarus-Pahonia pulled 3, Croatia 5, Georgia-Georgians 1, and Russia-Voronezh 6). Three out of four Teams not meeting an age limit drew lots from the pool 13+14+15+16 (Iran-Black Intelligence pulled 13, Iran-Velayat 16, and Iran-Amordad 15). The lots remaining in both pools (2+4+14) were merged with the bulk of lots (7+8+9+10+11+12), and other teams drew lots from such a pool of 9 lots.

#### 18 Teams (5th IYNT 2017)

SF | Group A | Group B | Group C | Group D | Group E | Group F |
---|---|---|---|---|---|---|

1 | [1 7 13] | [2 8 14] | [3 9 15] | [4 10 16] | [5 11 17] | [6 12 18] |

2 | [8 18 4] | [9 13 5] | [10 14 6] | [11 15 1] | [12 16 2] | [7 17 3] |

3 | [13 3 11] | [14 4 12] | [15 5 7] | [16 6 8] | [17 1 9] | [18 2 10] |

4 | [r1+r12+r13] [10 9 17] | [r2+r11+r14] [2 7 8] | [r3+r10+r15] [5 3 16] | [r4+r9+r16] [12 6 1] | [r5+r8+r17] [13 8 4] | [r6+r7+r18] [11 15 14] |

sF | [r1+r6+r7] [14 3 17] | [r2+r5+r8] [7 18 16] | [r3+r4+r9] [15 6 4] | --- | --- | --- |

Fin | [vA+vB+vC] [6 16 17] | --- | --- | --- | --- | --- |

An optimzed bracket for 18 Teams was used. Country represented by six Teams (China) drew lots from one pool. Country represented by three Teams (Russia) drew lots from another pool. The remaining lots were merged.

#### 15 Teams (6th IYNT 2018)

SF | Group A | Group B | Group C | Group D | Group E |
---|---|---|---|---|---|

SF 1 | [1 6 11] | [2 7 12] | [3 8 13] | [4 9 14] | [5 10 15] |

SF 2 | [7 15 3] | [8 11 4] | [9 12 5] | [10 13 1] | [6 14 2] |

SF 3 | [11 3 10] | [12 4 6] | [13 5 7] | [14 1 8] | [15 2 9] |

SF 4 | [r1+r10+r11] [5 15 2] | [r2+r9+r12] [9 11 7] | [r3+r8+r13] [4 14 12] | [r4+r7+r14] [8 13 6] | [r5+r6+r15] [1 3 10] |

sF | [r1+r6+r7] [6 2 14] | [r2+r5+r8] [3 9 4] | [r3+r4+r9] [10 13 7] | --- | --- |

Fin | [vA+vB+vC] [10 4 2] | --- | --- | --- | --- |

An optimized bracket for 15 Teams was used. Captains of Russian Teams (country represented by four Teams) were invited to the stage together with the youngest IYNT participant Teodora Visarieva (Bulgaria-Awakward Turtles) who was asked to select a random Russian captain. The captain selected one of three bags with lots (Georgian souvernir horns), drew the lot and selected the next Russian captain to draw lots. When all Russian Teams drew lots from the pool 10+11+12+13+14+15, countries represented by two Teams consecutively drew lots from two remaining pools. Eventually, lot 2 remained in Bag 1, lot 6+8+9 remained in Bag 2, and lot 14 remained in Bag 3. These were merged and countries represented by one Team, drew lots from a combined pool. Belarus skipped the ceremony and obtained the last remaining lot (14).