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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 4 |
| 3 | 64 |
| 4 | 400 |
| 5 | 1600 |
| 6 | 4900 |
| 7 | 12544 |
| 8 | 28224 |
| 9 | 57600 |
| 10 | 108900 |
| 11 | 193600 |
| 12 | 327184 |
| 13 | 529984 |
| 14 | 828100 |
| 15 | 1254400 |
| 16 | 1849600 |
| 17 | 2663424 |
| 18 | 3755844 |
| 19 | 5198400 |
| 20 | 7075600 |
| 21 | 9486400 |
| 22 | 12545764 |
| 23 | 16386304 |
| 24 | 21160000 |
| 25 | 27040000 |
| 26 | 34222500 |
| 27 | 42928704 |
| 28 | 53406864 |
| 29 | 65934400 |
| 30 | 80820100 |
| 31 | 98406400 |
[0,0,4,64,400,1600,4900,12544,28224,57600,108900, 193600,327184,529984,828100,1254400,1849600, 2663424,3755844,5198400,7075600,9486400,12545764, 16386304,21160000,27040000,34222500,42928704, 53406864,65934400,80820100,98406400] |