n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 4 |
3 | 30 |
4 | 440 |
5 | 9892 |
6 | 331950 |
7 | 15121926 |
8 | 915201732 |
9 | 70120569074 |
10 | 6696969703276 |
11 | 774618119733020 |
12 | 107284227278413622 |
13 | 17455779156567652806 |
14 | 3307802489634916900474 |
15 | 720231707823173636419042 |
16 | 178973636259170839478327332 |
17 | 50249140887232774758578932120 |
[1,1,4,30,440,9892,331950,15121926,915201732, 70120569074,6696969703276,774618119733020, 107284227278413622,17455779156567652806, 3307802489634916900474,720231707823173636419042, 178973636259170839478327332, 50249140887232774758578932120] |