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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 66 |
| 3 | 220 |
| 4 | 495 |
| 5 | 792 |
| 6 | 924 |
| 7 | 792 |
| 8 | 495 |
| 9 | 232 |
| 10 | 198 |
| 11 | 672 |
| 12 | 1981 |
| 13 | 3960 |
| 14 | 5544 |
| 15 | 5544 |
| 16 | 3960 |
| 17 | 1980 |
| 18 | 726 |
| 19 | 792 |
| 20 | 2982 |
| 21 | 7920 |
| 22 | 13860 |
| 23 | 16632 |
| 24 | 13860 |
| 25 | 7920 |
| 26 | 2970 |
| 27 | 880 |
| 28 | 2046 |
| 29 | 7920 |
| 30 | 18480 |
| 31 | 27720 |
| 32 | 27720 |
| 33 | 18480 |
| 34 | 7920 |
| 35 | 1980 |
| 36 | 727 |
| 37 | 4092 |
| 38 | 14520 |
| 39 | 29700 |
| 40 | 38610 |
| 41 | 33264 |
| 42 | 19404 |
| 43 | 7920 |
| 44 | 2475 |
| 45 | 1584 |
| 46 | 6996 |
| 47 | 22584 |
| 48 | 43560 |
| 49 | 55440 |
| 50 | 49896 |
[1,12,66,220,495,792,924,792,495,232,198,672,1981, 3960,5544,5544,3960,1980,726,792,2982,7920,13860, 16632,13860,7920,2970,880,2046,7920,18480,27720, 27720,18480,7920,1980,727,4092,14520,29700,38610, 33264,19404,7920,2475,1584,6996,22584,43560,55440, 49896] |