n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 4 |
4 | 28 |
5 | 301 |
6 | 4466 |
7 | 84974 |
8 | 1974904 |
9 | 54233540 |
10 | 1718280152 |
11 | 61695193880 |
12 | 2475688513024 |
13 | 109797950475448 |
14 | 5333253012414224 |
15 | 281576039542538368 |
16 | 16055279332196218624 |
17 | 983264280857581866112 |
18 | 64369946360185677026048 |
19 | 4485859513184032011682304 |
20 | 331558482325457407154881024 |
[1,1,4,28,301,4466,84974,1974904,54233540, 1718280152,61695193880,2475688513024, 109797950475448,5333253012414224, 281576039542538368,16055279332196218624, 983264280857581866112,64369946360185677026048, 4485859513184032011682304, 331558482325457407154881024] |