n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 4 |
3 | 25 |
4 | 230 |
5 | 2786 |
6 | 42112 |
7 | 764296 |
8 | 16209916 |
9 | 393678856 |
10 | 10777609556 |
11 | 328466815964 |
12 | 11031378197776 |
13 | 404830360798072 |
14 | 16118917055902312 |
15 | 692126238230304616 |
16 | 31882272572881781648 |
17 | 1568365865590875789824 |
18 | 82061348851406564851312 |
[1,1,4,25,230,2786,42112,764296,16209916, 393678856,10777609556,328466815964,11031378197776, 404830360798072,16118917055902312, 692126238230304616,31882272572881781648, 1568365865590875789824,82061348851406564851312] |