n | a(n) |
---|---|
0 | 1 |
1 | 6 |
2 | 18 |
3 | 48 |
4 | 126 |
5 | 330 |
6 | 864 |
7 | 2262 |
8 | 5922 |
9 | 15504 |
10 | 40590 |
11 | 106266 |
12 | 278208 |
13 | 728358 |
14 | 1906866 |
15 | 4992240 |
16 | 13069854 |
17 | 34217322 |
18 | 89582112 |
19 | 234529014 |
20 | 614004930 |
21 | 1607485776 |
22 | 4208452398 |
23 | 11017871418 |
24 | 28845161856 |
25 | 75517614150 |
26 | 197707680594 |
[1,6,18,48,126,330,864,2262,5922,15504,40590, 106266,278208,728358,1906866,4992240,13069854, 34217322,89582112,234529014,614004930,1607485776, 4208452398,11017871418,28845161856,75517614150, 197707680594] |