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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 1 |
| 7 | 3 |
| 8 | 6 |
| 9 | 10 |
| 10 | 1 |
| 11 | 4 |
| 12 | 10 |
| 13 | 20 |
| 14 | 35 |
| 15 | 1 |
| 16 | 5 |
| 17 | 15 |
| 18 | 35 |
| 19 | 70 |
| 20 | 121 |
| 21 | 1 |
| 22 | 6 |
| 23 | 21 |
| 24 | 56 |
| 25 | 126 |
| 26 | 246 |
| 27 | 426 |
| 28 | 1 |
| 29 | 7 |
| 30 | 28 |
| 31 | 84 |
| 32 | 210 |
| 33 | 455 |
| 34 | 875 |
| 35 | 1520 |
| 36 | 1 |
| 37 | 8 |
| 38 | 36 |
| 39 | 120 |
| 40 | 330 |
| 41 | 784 |
| 42 | 1652 |
| 43 | 3144 |
| 44 | 5475 |
| 45 | 1 |
| 46 | 9 |
| 47 | 45 |
| 48 | 165 |
| 49 | 495 |
| 50 | 1278 |
| 51 | 2922 |
| 52 | 6030 |
| 53 | 11385 |
| 54 | 19855 |
| 55 | 1 |
| 56 | 10 |
[1,1,1,1,2,3,1,3,6,10,1,4,10,20,35,1,5,15,35,70, 121,1,6,21,56,126,246,426,1,7,28,84,210,455,875, 1520,1,8,36,120,330,784,1652,3144,5475,1,9,45,165, 495,1278,2922,6030,11385,19855,1,10] |