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| n | a(n) |
|---|---|
| 11 | 1 |
| 12 | 9 |
| 13 | 44 |
| 14 | 163 |
| 15 | 519 |
| 16 | 1502 |
| 17 | 4081 |
| 18 | 10625 |
| 19 | 26836 |
| 20 | 66278 |
| 21 | 160934 |
| 22 | 385647 |
| 23 | 914426 |
| 24 | 2149634 |
| 25 | 5017105 |
| 26 | 11638062 |
| 27 | 26853653 |
| 28 | 61674487 |
| 29 | 141063327 |
| 30 | 321453345 |
| 31 | 730085764 |
| 32 | 1653165271 |
| 33 | 3733016952 |
| 34 | 8408241791 |
| 35 | 18894670248 |
| 36 | 42368155842 |
| 37 | 94814369316 |
| 38 | 211789296206 |
| 39 | 472262524451 |
[1,9,44,163,519,1502,4081,10625,26836,66278, 160934,385647,914426,2149634,5017105,11638062, 26853653,61674487,141063327,321453345,730085764, 1653165271,3733016952,8408241791,18894670248, 42368155842,94814369316,211789296206,472262524451] |