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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 3 |
| 6 | 1 |
| 7 | 4 |
| 8 | 6 |
| 9 | 20 |
| 10 | 13 |
| 11 | 48 |
| 12 | 50 |
| 13 | 175 |
| 14 | 141 |
| 15 | 512 |
| 16 | 481 |
| 17 | 1719 |
| 18 | 1491 |
| 19 | 5400 |
| 20 | 4929 |
| 21 | 17776 |
| 22 | 15840 |
| 23 | 57420 |
| 24 | 52079 |
| 25 | 188656 |
| 26 | 169989 |
| 27 | 617176 |
| 28 | 559834 |
| 29 | 2033175 |
| 30 | 1842041 |
| 31 | 6697744 |
| 32 | 6085950 |
| 33 | 22139780 |
| 34 | 20123989 |
| 35 | 73262232 |
| 36 | 66697354 |
| 37 | 242931321 |
| 38 | 221314299 |
| 39 | 806516560 |
[1,1,0,0,1,3,1,4,6,20,13,48,50,175,141,512,481, 1719,1491,5400,4929,17776,15840,57420,52079, 188656,169989,617176,559834,2033175,1842041, 6697744,6085950,22139780,20123989,73262232, 66697354,242931321,221314299,806516560] |