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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 9 |
| 6 | 22 |
| 7 | 59 |
| 8 | 167 |
| 9 | 490 |
| 10 | 1486 |
| 11 | 4639 |
| 12 | 14805 |
| 13 | 48107 |
| 14 | 158808 |
| 15 | 531469 |
| 16 | 1799659 |
| 17 | 6157068 |
| 18 | 21258104 |
| 19 | 73996100 |
| 20 | 259451116 |
| 21 | 915695102 |
| 22 | 3251073303 |
| 23 | 11605141649 |
| 24 | 41631194766 |
| 25 | 150021775417 |
| 26 | 542875459724 |
| 27 | 1972050156181 |
| 28 | 7189259574618 |
| 29 | 26295934251565 |
| 30 | 96478910768821 |
| 31 | 354998461378719 |
| 32 | 1309755903513481 |
[1,1,1,2,4,9,22,59,167,490,1486,4639,14805,48107, 158808,531469,1799659,6157068,21258104,73996100, 259451116,915695102,3251073303,11605141649, 41631194766,150021775417,542875459724, 1972050156181,7189259574618,26295934251565, 96478910768821,354998461378719,1309755903513481] |