n | a(n) |
---|---|
1 | 1 |
2 | 0 |
3 | 0 |
4 | 2 |
5 | 10 |
6 | 4 |
7 | 28 |
8 | 20 |
9 | 56 |
10 | 72 |
11 | 200 |
12 | 644 |
13 | 2940 |
14 | 9152 |
15 | 39200 |
16 | 166100 |
17 | 739924 |
18 | 3586840 |
19 | 18640500 |
20 | 107580592 |
21 | 547737844 |
22 | 3080550788 |
[1,0,0,2,10,4,28,20,56,72,200,644,2940,9152,39200, 166100,739924,3586840,18640500,107580592, 547737844,3080550788] |