n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 4 |
3 | 12 |
4 | 40 |
5 | 154 |
6 | 590 |
7 | 2291 |
8 | 9523 |
9 | 39351 |
10 | 164720 |
11 | 711336 |
12 | 3073150 |
13 | 13376333 |
14 | 59305585 |
15 | 263251753 |
16 | 1174914851 |
17 | 5305026397 |
18 | 23991323059 |
19 | 108935348192 |
20 | 498558014381 |
21 | 2285348450639 |
22 | 10508708646670 |
23 | 48595333492782 |
24 | 225057299921016 |
25 | 1044912400895195 |
26 | 4871739738152142 |
27 | 22745133446781661 |
[1,1,4,12,40,154,590,2291,9523,39351,164720, 711336,3073150,13376333,59305585,263251753, 1174914851,5305026397,23991323059,108935348192, 498558014381,2285348450639,10508708646670, 48595333492782,225057299921016,1044912400895195, 4871739738152142,22745133446781661] |