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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 21 |
| 4 | 56 |
| 5 | 126 |
| 6 | 252 |
| 7 | 462 |
| 8 | 792 |
| 9 | 1287 |
| 10 | 2001 |
| 11 | 2992 |
| 12 | 4317 |
| 13 | 6027 |
| 14 | 8162 |
| 15 | 10746 |
| 16 | 13782 |
| 17 | 17247 |
| 18 | 21087 |
| 19 | 25212 |
| 20 | 29496 |
| 21 | 33787 |
| 22 | 37917 |
| 23 | 41712 |
| 24 | 45002 |
| 25 | 47631 |
| 26 | 49467 |
| 27 | 50412 |
| 28 | 50412 |
| 29 | 49467 |
| 30 | 47631 |
| 31 | 45002 |
| 32 | 41712 |
| 33 | 37917 |
| 34 | 33787 |
| 35 | 29496 |
| 36 | 25212 |
| 37 | 21087 |
| 38 | 17247 |
| 39 | 13782 |
| 40 | 10746 |
| 41 | 8162 |
| 42 | 6027 |
| 43 | 4317 |
| 44 | 2992 |
| 45 | 2001 |
| 46 | 1287 |
| 47 | 792 |
| 48 | 462 |
| 49 | 252 |
| 50 | 126 |
| 51 | 56 |
| 52 | 21 |
| 53 | 6 |
| 54 | 1 |
[1,6,21,56,126,252,462,792,1287,2001,2992,4317, 6027,8162,10746,13782,17247,21087,25212,29496, 33787,37917,41712,45002,47631,49467,50412,50412, 49467,47631,45002,41712,37917,33787,29496,25212, 21087,17247,13782,10746,8162,6027,4317,2992,2001, 1287,792,462,252,126,56,21,6,1] |