The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -2 |
| 3 | 1 |
| 4 | 0 |
| 5 | 6 |
| 6 | 1 |
| 7 | 6 |
| 8 | -10 |
| 9 | -20 |
| 10 | 1 |
| 11 | 16 |
| 12 | 70 |
| 13 | 0 |
| 14 | 70 |
| 15 | 1 |
| 16 | 30 |
| 17 | 630 |
| 18 | 924 |
| 19 | 198 |
| 20 | -252 |
| 21 | 1 |
| 22 | 48 |
| 23 | 2310 |
| 24 | 28672 |
| 25 | 12870 |
| 26 | 0 |
| 27 | 924 |
| 28 | 1 |
| 29 | 70 |
| 30 | 6006 |
| 31 | 204204 |
| 32 | 1385670 |
| 33 | 184756 |
| 34 | -4420 |
| 35 | -3432 |
| 36 | 1 |
| 37 | 96 |
| 38 | 12870 |
| 39 | 860160 |
| 40 | 19122246 |
| 41 | 69206016 |
| 42 | 2704156 |
| 43 | 0 |
| 44 | 12870 |
| 45 | 1 |
| 46 | 126 |
| 47 | 24310 |
| 48 | 2704156 |
| 49 | 130378950 |
| 50 | 1848483780 |
| 51 | 3528923580 |
| 52 | 40116600 |
| 53 | 104006 |
| 54 | -48620 |
[1,1,-2,1,0,6,1,6,-10,-20,1,16,70,0,70,1,30,630, 924,198,-252,1,48,2310,28672,12870,0,924,1,70, 6006,204204,1385670,184756,-4420,-3432,1,96,12870, 860160,19122246,69206016,2704156,0,12870,1,126, 24310,2704156,130378950,1848483780,3528923580, 40116600,104006,-48620] |