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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 48 |
| 6 | 424 |
| 7 | 1976 |
| 8 | 6616 |
| 9 | 17852 |
| 10 | 41544 |
| 11 | 86660 |
| 12 | 166288 |
| 13 | 298616 |
| 14 | 508200 |
| 15 | 827168 |
| 16 | 1296744 |
| 17 | 1968676 |
| 18 | 2907016 |
| 19 | 4189772 |
| 20 | 5910944 |
| 21 | 8182400 |
| 22 | 11136168 |
| 23 | 14926536 |
| 24 | 19732600 |
| 25 | 25760588 |
| 26 | 33246664 |
| 27 | 42459476 |
| 28 | 53703216 |
| 29 | 67320392 |
| 30 | 83695144 |
[0,0,0,0,48,424,1976,6616,17852,41544,86660, 166288,298616,508200,827168,1296744,1968676, 2907016,4189772,5910944,8182400,11136168,14926536, 19732600,25760588,33246664,42459476,53703216, 67320392,83695144] |