n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 1 |
3 | 2 |
4 | 5 |
5 | 19 |
6 | 90 |
7 | 520 |
8 | 3475 |
9 | 26550 |
10 | 228050 |
11 | 2177020 |
12 | 22860090 |
13 | 261870070 |
14 | 3249793360 |
15 | 43432062300 |
16 | 621911561150 |
17 | 9498946124800 |
18 | 154152712434600 |
19 | 2648808048264400 |
20 | 48043086765929200 |
21 | 917249983543337400 |
[0,1,1,2,5,19,90,520,3475,26550,228050,2177020, 22860090,261870070,3249793360,43432062300, 621911561150,9498946124800,154152712434600, 2648808048264400,48043086765929200, 917249983543337400] |