n | a(n) |
---|---|
1 | 0 |
2 | 1 |
3 | 1 |
4 | 4 |
5 | 12 |
6 | 45 |
7 | 144 |
8 | 512 |
9 | 1813 |
10 | 6579 |
11 | 23808 |
12 | 87380 |
13 | 322560 |
14 | 1198665 |
15 | 4473647 |
16 | 16777216 |
17 | 63160320 |
18 | 238612920 |
19 | 904200192 |
20 | 3435973836 |
21 | 13089411609 |
22 | 49977848925 |
23 | 191219367936 |
24 | 733007751680 |
25 | 2814749599332 |
26 | 10825961287995 |
27 | 41699995927744 |
28 | 160842843834660 |
[0,1,1,4,12,45,144,512,1813,6579,23808,87380, 322560,1198665,4473647,16777216,63160320, 238612920,904200192,3435973836,13089411609, 49977848925,191219367936,733007751680, 2814749599332,10825961287995,41699995927744, 160842843834660] |