n | a(n) |
---|---|
1 | 1 |
2 | 4 |
3 | 18 |
4 | 62 |
5 | 210 |
6 | 666 |
7 | 2063 |
8 | 6226 |
9 | 18484 |
10 | 54100 |
11 | 156620 |
12 | 449268 |
13 | 1278981 |
14 | 3617544 |
15 | 10175590 |
16 | 28485218 |
17 | 79406350 |
18 | 220536910 |
19 | 610487875 |
20 | 1684974790 |
21 | 4638298536 |
22 | 12737460744 |
23 | 34902844728 |
24 | 95449821672 |
25 | 260554112425 |
26 | 710056257196 |
[1,4,18,62,210,666,2063,6226,18484,54100,156620, 449268,1278981,3617544,10175590,28485218,79406350, 220536910,610487875,1684974790,4638298536, 12737460744,34902844728,95449821672,260554112425, 710056257196] |