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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 4 |
| 2 | 0 |
| 3 | 0 |
| 4 | 28 |
| 5 | 120 |
| 6 | 324 |
| 7 | 700 |
| 8 | 1320 |
| 9 | 2268 |
| 10 | 3640 |
| 11 | 5544 |
| 12 | 8100 |
| 13 | 11440 |
| 14 | 15708 |
| 15 | 21060 |
| 16 | 27664 |
| 17 | 35700 |
| 18 | 45360 |
| 19 | 56848 |
| 20 | 70380 |
| 21 | 86184 |
| 22 | 104500 |
| 23 | 125580 |
| 24 | 149688 |
| 25 | 177100 |
| 26 | 208104 |
| 27 | 243000 |
| 28 | 282100 |
| 29 | 325728 |
| 30 | 374220 |
| 31 | 427924 |
| 32 | 487200 |
| 33 | 552420 |
| 34 | 623968 |
[0,4,0,0,28,120,324,700,1320,2268,3640,5544,8100, 11440,15708,21060,27664,35700,45360,56848,70380, 86184,104500,125580,149688,177100,208104,243000, 282100,325728,374220,427924,487200,552420,623968] |