n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 1 |
3 | 3 |
4 | 9 |
5 | 42 |
6 | 232 |
7 | 1528 |
8 | 11611 |
9 | 99851 |
10 | 958562 |
11 | 10160756 |
12 | 117864769 |
13 | 1485096082 |
14 | 20197306709 |
15 | 294880677942 |
16 | 4600138575888 |
17 | 76362300359741 |
18 | 1343976486331426 |
19 | 24997962645764523 |
20 | 489960067856984639 |
[1,1,1,3,9,42,232,1528,11611,99851,958562, 10160756,117864769,1485096082,20197306709, 294880677942,4600138575888,76362300359741, 1343976486331426,24997962645764523, 489960067856984639] |