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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 30 |
| 8 | 120 |
| 9 | 294 |
| 10 | 552 |
| 11 | 894 |
| 12 | 1320 |
| 13 | 1830 |
| 14 | 2424 |
| 15 | 3102 |
| 16 | 3864 |
| 17 | 4710 |
| 18 | 5640 |
| 19 | 6654 |
| 20 | 7752 |
| 21 | 8934 |
| 22 | 10200 |
| 23 | 11550 |
| 24 | 12984 |
| 25 | 14502 |
| 26 | 16104 |
| 27 | 17790 |
| 28 | 19560 |
| 29 | 21414 |
| 30 | 23352 |
| 31 | 25374 |
| 32 | 27480 |
| 33 | 29670 |
| 34 | 31944 |
| 35 | 34302 |
| 36 | 36744 |
| 37 | 39270 |
| 38 | 41880 |
| 39 | 44574 |
| 40 | 47352 |
| 41 | 50214 |
| 42 | 53160 |
| 43 | 56190 |
| 44 | 59304 |
| 45 | 62502 |
[0,0,0,0,0,0,30,120,294,552,894,1320,1830,2424, 3102,3864,4710,5640,6654,7752,8934,10200,11550, 12984,14502,16104,17790,19560,21414,23352,25374, 27480,29670,31944,34302,36744,39270,41880,44574, 47352,50214,53160,56190,59304,62502] |