n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 2 |
3 | 4 |
4 | 12 |
5 | 43 |
6 | 160 |
7 | 668 |
8 | 3098 |
9 | 15465 |
10 | 83100 |
11 | 477651 |
12 | 2914505 |
13 | 18795814 |
14 | 127790544 |
15 | 911448954 |
16 | 6808162094 |
17 | 53067398065 |
18 | 430956571977 |
19 | 3636314065247 |
20 | 31841519540324 |
21 | 288664242344692 |
22 | 2706949104147162 |
23 | 26205222185730884 |
24 | 261681461422075548 |
25 | 2691088457402830312 |
[1,1,2,4,12,43,160,668,3098,15465,83100,477651, 2914505,18795814,127790544,911448954,6808162094, 53067398065,430956571977,3636314065247, 31841519540324,288664242344692,2706949104147162, 26205222185730884,261681461422075548, 2691088457402830312] |