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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 6 |
| 4 | 4 |
| 5 | 1 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 68 |
| 11 | 640 |
| 12 | 2644 |
| 13 | 6320 |
| 14 | 9773 |
| 15 | 10304 |
| 16 | 7788 |
| 17 | 4352 |
| 18 | 1820 |
| 19 | 560 |
| 20 | 120 |
| 21 | 16 |
| 22 | 1 |
| 23 | 0 |
| 24 | 0 |
| 25 | 0 |
| 26 | 0 |
| 27 | 0 |
| 28 | 0 |
| 29 | 462 |
| 30 | 12456 |
| 31 | 162810 |
| 32 | 1370172 |
| 33 | 8316297 |
| 34 | 38643624 |
| 35 | 142444695 |
| 36 | 426043278 |
| 37 | 1049742000 |
| 38 | 2153912760 |
| 39 | 3711426624 |
| 40 | 5409742482 |
| 41 | 6716638430 |
| 42 | 7153883766 |
| 43 | 6584406876 |
| 44 | 5274811392 |
| 45 | 3701882250 |
| 46 | 2287146006 |
| 47 | 1247224353 |
| 48 | 600206400 |
| 49 | 254134359 |
| 50 | 94140796 |
| 51 | 30260304 |
| 52 | 8347680 |
| 53 | 1947792 |
| 54 | 376992 |
| 55 | 58905 |
| 56 | 7140 |
| 57 | 630 |
| 58 | 36 |
| 59 | 1 |
[0,0,6,4,1,0,0,0,0,68,640,2644,6320,9773,10304, 7788,4352,1820,560,120,16,1,0,0,0,0,0,0,462,12456, 162810,1370172,8316297,38643624,142444695, 426043278,1049742000,2153912760,3711426624, 5409742482,6716638430,7153883766,6584406876, 5274811392,3701882250,2287146006,1247224353, 600206400,254134359,94140796,30260304,8347680, 1947792,376992,58905,7140,630,36,1] |