n | a(n) |
---|---|
2 | 2 |
3 | 20 |
4 | 135 |
5 | 770 |
6 | 4004 |
7 | 19656 |
8 | 92820 |
9 | 426360 |
10 | 1918620 |
11 | 8498776 |
12 | 37182145 |
13 | 161056350 |
14 | 691945800 |
15 | 2952675600 |
16 | 12527780760 |
17 | 52895074320 |
18 | 222399744300 |
19 | 931689977400 |
20 | 3890668331550 |
21 | 16201562020644 |
22 | 67298796085752 |
23 | 278927990831600 |
24 | 1153747598439800 |
25 | 4763749454427600 |
26 | 19637233862140440 |
[2,20,135,770,4004,19656,92820,426360,1918620, 8498776,37182145,161056350,691945800,2952675600, 12527780760,52895074320,222399744300,931689977400, 3890668331550,16201562020644,67298796085752, 278927990831600,1153747598439800,4763749454427600, 19637233862140440] |