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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 15 |
| 6 | 46 |
| 7 | 149 |
| 8 | 495 |
| 9 | 1682 |
| 10 | 5806 |
| 11 | 20322 |
| 12 | 71919 |
| 13 | 256936 |
| 14 | 925298 |
| 15 | 3355509 |
| 16 | 12242471 |
| 17 | 44906105 |
| 18 | 165503745 |
| 19 | 612575796 |
| 20 | 2276024836 |
| 21 | 8485972958 |
| 22 | 31739314999 |
| 23 | 119054638380 |
| 24 | 447759005393 |
| 25 | 1688108544222 |
| 26 | 6378722610280 |
| 27 | 24153083898505 |
| 28 | 91633201241544 |
| 29 | 348270745289976 |
| 30 | 1325907389447937 |
| 31 | 5055855150302197 |
| 32 | 19307179347881167 |
| 33 | 73832434701139921 |
| 34 | 282712142418209398 |
| 35 | 1083873025643898568 |
| 36 | 4160250292584533013 |
| 37 | 15986022831150313756 |
| 38 | 61491665982535018897 |
[1,1,1,2,5,15,46,149,495,1682,5806,20322,71919, 256936,925298,3355509,12242471,44906105,165503745, 612575796,2276024836,8485972958,31739314999, 119054638380,447759005393,1688108544222, 6378722610280,24153083898505,91633201241544, 348270745289976,1325907389447937,5055855150302197, 19307179347881167,73832434701139921, 282712142418209398,1083873025643898568, 4160250292584533013,15986022831150313756, 61491665982535018897] |