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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 5 |
| 4 | 10 |
| 5 | 24 |
| 6 | 50 |
| 7 | 104 |
| 8 | 212 |
| 9 | 436 |
| 10 | 886 |
| 11 | 1792 |
| 12 | 3631 |
| 13 | 7319 |
| 14 | 14771 |
| 15 | 29737 |
| 16 | 59826 |
| 17 | 120322 |
| 18 | 241753 |
| 19 | 485652 |
| 20 | 974989 |
| 21 | 1956815 |
| 22 | 3926087 |
| 23 | 7874899 |
| 24 | 15791397 |
| 25 | 31660311 |
| 26 | 63463119 |
| 27 | 127190437 |
| 28 | 254873548 |
| 29 | 510663633 |
| 30 | 1023044286 |
| 31 | 2049300991 |
| 32 | 4104631710 |
| 33 | 8220611286 |
[0,0,1,5,10,24,50,104,212,436,886,1792,3631,7319, 14771,29737,59826,120322,241753,485652,974989, 1956815,3926087,7874899,15791397,31660311, 63463119,127190437,254873548,510663633,1023044286, 2049300991,4104631710,8220611286] |