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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 110 |
| 4 | 330 |
| 5 | 462 |
| 6 | 1320 |
| 7 | 2640 |
| 8 | 3960 |
| 9 | 7150 |
| 10 | 9240 |
| 11 | 15840 |
| 12 | 20900 |
| 13 | 29040 |
| 14 | 36960 |
| 15 | 53614 |
| 16 | 66330 |
| 17 | 87120 |
| 18 | 104280 |
| 19 | 134640 |
| 20 | 158532 |
| 21 | 203280 |
| 22 | 227040 |
| 23 | 294030 |
| 24 | 327360 |
| 25 | 414414 |
| 26 | 454080 |
| 27 | 563310 |
| 28 | 596640 |
| 29 | 728640 |
| 30 | 798600 |
| 31 | 975150 |
| 32 | 1025640 |
| 33 | 1254110 |
[1,0,0,110,330,462,1320,2640,3960,7150,9240,15840, 20900,29040,36960,53614,66330,87120,104280,134640, 158532,203280,227040,294030,327360,414414,454080, 563310,596640,728640,798600,975150,1025640, 1254110] |