n | a(n) |
---|---|
1 | 1 |
2 | 2 |
3 | 7 |
4 | 20 |
5 | 68 |
6 | 224 |
7 | 780 |
8 | 2720 |
9 | 9709 |
10 | 34918 |
11 | 127100 |
12 | 465920 |
13 | 1720740 |
14 | 6390930 |
15 | 23860928 |
16 | 89477120 |
17 | 336860180 |
18 | 1272578048 |
19 | 4822419420 |
20 | 18325176316 |
21 | 69810262080 |
22 | 266548209850 |
23 | 1019836872140 |
24 | 3909374443520 |
25 | 15011998757888 |
[1,2,7,20,68,224,780,2720,9709,34918,127100, 465920,1720740,6390930,23860928,89477120, 336860180,1272578048,4822419420,18325176316, 69810262080,266548209850,1019836872140, 3909374443520,15011998757888] |