n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 4 |
3 | 15 |
4 | 61 |
5 | 249 |
6 | 1040 |
7 | 4363 |
8 | 18424 |
9 | 78014 |
10 | 331099 |
11 | 1407080 |
12 | 5985505 |
13 | 25477399 |
14 | 108493103 |
15 | 462147381 |
16 | 1969025286 |
17 | 8390475609 |
18 | 35757524184 |
19 | 152398429323 |
20 | 649555719160 |
21 | 2768653475487 |
22 | 11801369554033 |
23 | 50304231997727 |
24 | 214428538858889 |
25 | 914039405714237 |
[1,1,4,15,61,249,1040,4363,18424,78014,331099, 1407080,5985505,25477399,108493103,462147381, 1969025286,8390475609,35757524184,152398429323, 649555719160,2768653475487,11801369554033, 50304231997727,214428538858889,914039405714237] |