n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 2 |
4 | 6 |
5 | 18 |
6 | 73 |
7 | 308 |
8 | 1484 |
9 | 7492 |
10 | 40010 |
11 | 220676 |
12 | 1253940 |
13 | 7282316 |
14 | 43096792 |
15 | 259019070 |
16 | 1577653196 |
17 | 9720170360 |
18 | 60492629435 |
19 | 379820431422 |
20 | 2403679290621 |
21 | 15319255038074 |
22 | 98255642978084 |
23 | 633833391637128 |
24 | 4110221883283079 |
25 | 26781322507739916 |
26 | 175268504233782739 |
[1,1,2,6,18,73,308,1484,7492,40010,220676,1253940, 7282316,43096792,259019070,1577653196,9720170360, 60492629435,379820431422,2403679290621, 15319255038074,98255642978084,633833391637128, 4110221883283079,26781322507739916, 175268504233782739] |