n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 4 |
3 | 28 |
4 | 278 |
5 | 3564 |
6 | 55928 |
7 | 1037708 |
8 | 22217720 |
9 | 539070560 |
10 | 14616331912 |
11 | 437960845728 |
12 | 14370870516352 |
13 | 512497731949840 |
14 | 19736969633949568 |
15 | 816329819676996352 |
16 | 36089654605723837664 |
17 | 1698341924904555647808 |
18 | 84761545323838638225152 |
19 | 4471847161631552852257472 |
[1,1,4,28,278,3564,55928,1037708,22217720, 539070560,14616331912,437960845728,14370870516352, 512497731949840,19736969633949568, 816329819676996352,36089654605723837664, 1698341924904555647808,84761545323838638225152, 4471847161631552852257472] |