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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 10 |
| 7 | 20 |
| 8 | 34 |
| 9 | 70 |
| 10 | 121 |
| 11 | 250 |
| 12 | 441 |
| 13 | 912 |
| 14 | 1630 |
| 15 | 3375 |
| 16 | 6092 |
| 17 | 12624 |
| 18 | 22961 |
| 19 | 47616 |
| 20 | 87136 |
| 21 | 180811 |
| 22 | 332549 |
| 23 | 690398 |
| 24 | 1275166 |
| 25 | 2648422 |
| 26 | 4909364 |
| 27 | 10199792 |
| 28 | 18966700 |
| 29 | 39416488 |
| 30 | 73497642 |
| 31 | 152777230 |
| 32 | 285569898 |
| 33 | 593717419 |
| 34 | 1112188817 |
| 35 | 2312672439 |
| 36 | 4340728280 |
[1,1,1,2,3,6,10,20,34,70,121,250,441,912,1630, 3375,6092,12624,22961,47616,87136,180811,332549, 690398,1275166,2648422,4909364,10199792,18966700, 39416488,73497642,152777230,285569898,593717419, 1112188817,2312672439,4340728280] |