n | a(n) |
---|---|
1 | 1 |
2 | 2 |
3 | 6 |
4 | 18 |
5 | 54 |
6 | 146 |
7 | 391 |
8 | 1081 |
9 | 3004 |
10 | 8320 |
11 | 22984 |
12 | 63424 |
13 | 175176 |
14 | 484113 |
15 | 1337721 |
16 | 3695886 |
17 | 10210702 |
18 | 28209954 |
19 | 77940078 |
20 | 215337554 |
21 | 594943087 |
22 | 1643728129 |
23 | 4541349672 |
24 | 12547013504 |
25 | 34665373744 |
26 | 95774808224 |
27 | 264610227072 |
[1,2,6,18,54,146,391,1081,3004,8320,22984,63424, 175176,484113,1337721,3695886,10210702,28209954, 77940078,215337554,594943087,1643728129, 4541349672,12547013504,34665373744,95774808224, 264610227072] |