The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 18 |
| 2 | 6 |
| 3 | 0 |
| 4 | 264 |
| 5 | 108 |
| 6 | 36 |
| 7 | 0 |
| 8 | 1344 |
| 9 | 654 |
| 10 | 252 |
| 11 | 12 |
| 12 | 6 |
| 13 | 4164 |
| 14 | 2772 |
| 15 | 1020 |
| 16 | 228 |
| 17 | 24 |
| 18 | 0 |
| 19 | 10038 |
| 20 | 7758 |
| 21 | 2424 |
| 22 | 516 |
| 23 | 72 |
| 24 | 24 |
| 25 | 0 |
| 26 | 21108 |
| 27 | 16188 |
| 28 | 6060 |
| 29 | 1128 |
| 30 | 156 |
| 31 | 0 |
| 32 | 0 |
| 33 | 0 |
| 34 | 39690 |
| 35 | 32022 |
| 36 | 13368 |
| 37 | 3654 |
| 38 | 432 |
| 39 | 48 |
| 40 | 0 |
| 41 | 0 |
| 42 | 0 |
| 43 | 68052 |
| 44 | 56616 |
| 45 | 22980 |
| 46 | 6084 |
| 47 | 888 |
| 48 | 120 |
| 49 | 12 |
| 50 | 0 |
| 51 | 0 |
| 52 | 0 |
[18,6,0,264,108,36,0,1344,654,252,12,6,4164,2772, 1020,228,24,0,10038,7758,2424,516,72,24,0,21108, 16188,6060,1128,156,0,0,0,39690,32022,13368,3654, 432,48,0,0,0,68052,56616,22980,6084,888,120,12,0, 0,0] |