n | a(n) |
---|---|
0 | 1 |
1 | 4 |
2 | 28 |
3 | 208 |
4 | 1552 |
5 | 11584 |
6 | 86464 |
7 | 645376 |
8 | 4817152 |
9 | 35955712 |
10 | 268377088 |
11 | 2003193856 |
12 | 14952042496 |
13 | 111603564544 |
14 | 833020346368 |
15 | 6217748512768 |
16 | 46409906716672 |
17 | 346408259682304 |
18 | 2585626450591744 |
19 | 19299378566004736 |
[1,4,28,208,1552,11584,86464,645376,4817152, 35955712,268377088,2003193856,14952042496, 111603564544,833020346368,6217748512768, 46409906716672,346408259682304,2585626450591744, 19299378566004736] |