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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 12 |
| 4 | 42 |
| 5 | 112 |
| 6 | 252 |
| 7 | 504 |
| 8 | 924 |
| 9 | 1584 |
| 10 | 2574 |
| 11 | 4004 |
| 12 | 6006 |
| 13 | 8736 |
| 14 | 12376 |
| 15 | 17136 |
| 16 | 23256 |
| 17 | 31008 |
| 18 | 40698 |
| 19 | 52668 |
| 20 | 67298 |
| 21 | 85008 |
| 22 | 106260 |
| 23 | 131560 |
| 24 | 161460 |
| 25 | 196560 |
| 26 | 237510 |
| 27 | 285012 |
| 28 | 339822 |
| 29 | 402752 |
| 30 | 474672 |
| 31 | 556512 |
| 32 | 649264 |
| 33 | 753984 |
| 34 | 871794 |
| 35 | 1003884 |
| 36 | 1151514 |
| 37 | 1316016 |
| 38 | 1498796 |
[0,2,12,42,112,252,504,924,1584,2574,4004,6006, 8736,12376,17136,23256,31008,40698,52668,67298, 85008,106260,131560,161460,196560,237510,285012, 339822,402752,474672,556512,649264,753984,871794, 1003884,1151514,1316016,1498796] |