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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 1 |
| 10 | 10 |
| 11 | 55 |
| 12 | 220 |
| 13 | 715 |
| 14 | 2002 |
| 15 | 5005 |
| 16 | 11440 |
| 17 | 24310 |
| 18 | 72930 |
| 19 | 1016158 |
| 20 | 18643560 |
| 21 | 258952330 |
| 22 | 2845739820 |
| 23 | 26177047270 |
| 24 | 209411148144 |
| 25 | 1495786618975 |
| 26 | 9722602868550 |
| 27 | 58373582056075 |
| 28 | 329869586346300 |
| 29 | 1861266055353705 |
[1,0,0,0,0,0,0,0,0,1,10,55,220,715,2002,5005, 11440,24310,72930,1016158,18643560,258952330, 2845739820,26177047270,209411148144,1495786618975, 9722602868550,58373582056075,329869586346300, 1861266055353705] |