n | a(n) |
---|---|
2 | 1 |
3 | 2 |
4 | 5 |
5 | 12 |
6 | 35 |
7 | 108 |
8 | 393 |
9 | 1666 |
10 | 8543 |
11 | 54190 |
12 | 436740 |
13 | 4565450 |
14 | 62930604 |
15 | 1156277748 |
16 | 28509174012 |
17 | 946786816168 |
18 | 42448800498744 |
19 | 2573207315483554 |
20 | 211180300735118954 |
21 | 23490473719472829824 |
22 | 3545759835559406756008 |
23 | 727077827560669587718290 |
[1,2,5,12,35,108,393,1666,8543,54190,436740, 4565450,62930604,1156277748,28509174012, 946786816168,42448800498744,2573207315483554, 211180300735118954,23490473719472829824, 3545759835559406756008,727077827560669587718290] |