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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 38 |
| 5 | 157 |
| 6 | 658 |
| 7 | 2892 |
| 8 | 13148 |
| 9 | 61075 |
| 10 | 290365 |
| 11 | 1402947 |
| 12 | 6881643 |
| 13 | 34184251 |
| 14 | 171674635 |
| 15 | 870572065 |
| 16 | 4452380910 |
| 17 | 22945034368 |
| 18 | 119053691259 |
| 19 | 621535445725 |
| 20 | 3262935266824 |
| 21 | 17216829337645 |
| 22 | 91266703043512 |
| 23 | 485870384685858 |
| 24 | 2596760622362760 |
| 25 | 13928930842625316 |
| 26 | 74965797677694568 |
| 27 | 404730005399499967 |
[1,1,3,11,38,157,658,2892,13148,61075,290365, 1402947,6881643,34184251,171674635,870572065, 4452380910,22945034368,119053691259,621535445725, 3262935266824,17216829337645,91266703043512, 485870384685858,2596760622362760, 13928930842625316,74965797677694568, 404730005399499967] |