n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 4 |
3 | 12 |
4 | 45 |
5 | 161 |
6 | 651 |
7 | 2575 |
8 | 10768 |
9 | 44901 |
10 | 193043 |
11 | 833057 |
12 | 3653939 |
13 | 16134813 |
14 | 71923457 |
15 | 322774583 |
16 | 1457954685 |
17 | 6622090289 |
18 | 30234131093 |
19 | 138642032594 |
20 | 638494794892 |
21 | 2951054790813 |
22 | 13687439364362 |
23 | 63680571279683 |
24 | 297128054833522 |
25 | 1390089493432837 |
26 | 6519295339621917 |
27 | 30644944208215577 |
[1,1,4,12,45,161,651,2575,10768,44901,193043, 833057,3653939,16134813,71923457,322774583, 1457954685,6622090289,30234131093,138642032594, 638494794892,2951054790813,13687439364362, 63680571279683,297128054833522,1390089493432837, 6519295339621917,30644944208215577] |