n | a(n) |
---|---|
0 | 0 |
1 | 2 |
2 | 20 |
3 | 186 |
4 | 1704 |
5 | 15510 |
6 | 140676 |
7 | 1273230 |
8 | 11508048 |
9 | 103919022 |
10 | 937787100 |
11 | 8458728630 |
12 | 76269112200 |
13 | 687496910490 |
14 | 6195793616460 |
15 | 55827244680930 |
16 | 502959206683296 |
17 | 4530723835554270 |
18 | 40809306881317068 |
19 | 367548287590324902 |
20 | 3310080578306654520 |
[0,2,20,186,1704,15510,140676,1273230,11508048, 103919022,937787100,8458728630,76269112200, 687496910490,6195793616460,55827244680930, 502959206683296,4530723835554270, 40809306881317068,367548287590324902, 3310080578306654520] |