n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 2 |
3 | 7 |
4 | 23 |
5 | 72 |
6 | 227 |
7 | 725 |
8 | 2332 |
9 | 7537 |
10 | 24465 |
11 | 79720 |
12 | 260633 |
13 | 854539 |
14 | 2808768 |
15 | 9252315 |
16 | 30536925 |
17 | 100959558 |
18 | 334301159 |
19 | 1108483583 |
20 | 3680134756 |
21 | 12231824111 |
22 | 40697552035 |
23 | 135536687436 |
24 | 451776392011 |
25 | 1507088458381 |
26 | 5031254413136 |
27 | 16807872970501 |
28 | 56185887793379 |
[1,1,2,7,23,72,227,725,2332,7537,24465,79720, 260633,854539,2808768,9252315,30536925,100959558, 334301159,1108483583,3680134756,12231824111, 40697552035,135536687436,451776392011, 1507088458381,5031254413136,16807872970501, 56185887793379] |