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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 1 |
| 10 | 0 |
| 11 | 3 |
| 12 | 0 |
| 13 | 6 |
| 14 | 0 |
| 15 | 10 |
| 16 | 0 |
| 17 | 15 |
| 18 | 1 |
| 19 | 21 |
| 20 | 4 |
| 21 | 28 |
| 22 | 10 |
| 23 | 36 |
| 24 | 20 |
| 25 | 45 |
| 26 | 35 |
| 27 | 56 |
| 28 | 56 |
| 29 | 71 |
| 30 | 84 |
| 31 | 93 |
| 32 | 120 |
| 33 | 126 |
| 34 | 165 |
| 35 | 175 |
| 36 | 221 |
| 37 | 246 |
| 38 | 292 |
| 39 | 346 |
| 40 | 385 |
| 41 | 483 |
| 42 | 511 |
| 43 | 666 |
| 44 | 686 |
| 45 | 906 |
| 46 | 932 |
| 47 | 1218 |
| 48 | 1278 |
| 49 | 1624 |
| 50 | 1761 |
| 51 | 2157 |
| 52 | 2427 |
| 53 | 2866 |
| 54 | 3333 |
| 55 | 3822 |
| 56 | 4551 |
[0,0,0,0,0,0,0,0,1,0,3,0,6,0,10,0,15,1,21,4,28,10, 36,20,45,35,56,56,71,84,93,120,126,165,175,221, 246,292,346,385,483,511,666,686,906,932,1218,1278, 1624,1761,2157,2427,2866,3333,3822,4551] |