n | a(n) |
---|---|
0 | 1 |
1 | 4 |
2 | 40 |
3 | 442 |
4 | 5136 |
5 | 61424 |
6 | 748462 |
7 | 9240480 |
8 | 115194720 |
9 | 1446820588 |
10 | 18279806600 |
11 | 232071505120 |
12 | 2958062657550 |
13 | 37831613904036 |
14 | 485233557808704 |
15 | 6239148779539472 |
16 | 80397210629541696 |
17 | 1037970502613332320 |
18 | 13423439565585274180 |
19 | 173859642721737225552 |
[1,4,40,442,5136,61424,748462,9240480,115194720, 1446820588,18279806600,232071505120,2958062657550, 37831613904036,485233557808704,6239148779539472, 80397210629541696,1037970502613332320, 13423439565585274180,173859642721737225552] |