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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 32 |
| 5 | 86 |
| 6 | 226 |
| 7 | 588 |
| 8 | 1596 |
| 9 | 4372 |
| 10 | 12065 |
| 11 | 33344 |
| 12 | 91344 |
| 13 | 249584 |
| 14 | 677896 |
| 15 | 1836048 |
| 16 | 5039672 |
| 17 | 13877256 |
| 18 | 38405640 |
| 19 | 106482832 |
| 20 | 296373672 |
| 21 | 826270666 |
| 22 | 2307068226 |
| 23 | 6445895588 |
| 24 | 17963996648 |
| 25 | 50028938140 |
| 26 | 139149397474 |
[1,2,5,12,32,86,226,588,1596,4372,12065,33344, 91344,249584,677896,1836048,5039672,13877256, 38405640,106482832,296373672,826270666,2307068226, 6445895588,17963996648,50028938140,139149397474] |