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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 6 |
| 7 | 21 |
| 8 | 52 |
| 9 | 121 |
| 10 | 226 |
| 11 | 431 |
| 12 | 688 |
| 13 | 1167 |
| 14 | 1726 |
| 15 | 2651 |
| 16 | 3696 |
| 17 | 5441 |
| 18 | 7140 |
| 19 | 10059 |
| 20 | 12941 |
| 21 | 17287 |
| 22 | 21710 |
| 23 | 28659 |
| 24 | 34724 |
| 25 | 44705 |
| 26 | 53942 |
| 27 | 67131 |
| 28 | 79828 |
| 29 | 99171 |
| 30 | 114846 |
| 31 | 140665 |
| 32 | 163317 |
| 33 | 194706 |
| 34 | 224008 |
| 35 | 266997 |
| 36 | 301436 |
| 37 | 356761 |
| 38 | 403846 |
[0,0,0,0,1,6,21,52,121,226,431,688,1167,1726,2651, 3696,5441,7140,10059,12941,17287,21710,28659, 34724,44705,53942,67131,79828,99171,114846,140665, 163317,194706,224008,266997,301436,356761,403846] |