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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 3 |
| 5 | 2 |
| 6 | 3 |
| 7 | 12 |
| 8 | 4 |
| 9 | 30 |
| 10 | 27 |
| 11 | 45 |
| 12 | 108 |
| 13 | 90 |
| 14 | 260 |
| 15 | 342 |
| 16 | 498 |
| 17 | 1115 |
| 18 | 1218 |
| 19 | 2709 |
| 20 | 3913 |
| 21 | 5949 |
| 22 | 11469 |
| 23 | 15262 |
| 24 | 28461 |
| 25 | 44556 |
| 26 | 68028 |
| 27 | 123243 |
| 28 | 178650 |
| 29 | 311337 |
| 30 | 498114 |
| 31 | 777996 |
| 32 | 1340603 |
| 33 | 2052765 |
| 34 | 3435906 |
| 35 | 5569902 |
| 36 | 8800392 |
| 37 | 14783823 |
| 38 | 23242761 |
| 39 | 38249550 |
| 40 | 62156709 |
[0,0,1,0,3,2,3,12,4,30,27,45,108,90,260,342,498, 1115,1218,2709,3913,5949,11469,15262,28461,44556, 68028,123243,178650,311337,498114,777996,1340603, 2052765,3435906,5569902,8800392,14783823,23242761, 38249550,62156709] |