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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 6 |
| 8 | 10 |
| 9 | 15 |
| 10 | 21 |
| 11 | 34 |
| 12 | 63 |
| 13 | 120 |
| 14 | 220 |
| 15 | 381 |
| 16 | 642 |
| 17 | 1102 |
| 18 | 1968 |
| 19 | 3615 |
| 20 | 6658 |
| 21 | 12090 |
| 22 | 21675 |
| 23 | 38820 |
| 24 | 70200 |
| 25 | 128466 |
| 26 | 236583 |
| 27 | 435453 |
| 28 | 798798 |
| 29 | 1462933 |
| 30 | 2684352 |
| 31 | 4945740 |
| 32 | 9145839 |
| 33 | 16942356 |
| 34 | 31388571 |
| 35 | 58140726 |
| 36 | 107753364 |
| 37 | 199993359 |
| 38 | 371852269 |
| 39 | 692375844 |
| 40 | 1290252474 |
[1,1,1,1,1,1,3,6,10,15,21,34,63,120,220,381,642, 1102,1968,3615,6658,12090,21675,38820,70200, 128466,236583,435453,798798,1462933,2684352, 4945740,9145839,16942356,31388571,58140726, 107753364,199993359,371852269,692375844, 1290252474] |