n | a(n) |
---|---|
3 | 0 |
4 | 0 |
5 | 4 |
6 | 6 |
7 | 4 |
8 | 16 |
9 | 46 |
10 | 84 |
11 | 224 |
12 | 558 |
13 | 1380 |
14 | 3418 |
15 | 9272 |
16 | 23340 |
17 | 58462 |
18 | 153503 |
19 | 404026 |
20 | 1041448 |
21 | 2725482 |
22 | 7226277 |
23 | 19073734 |
24 | 50488500 |
25 | 134468292 |
26 | 358721980 |
27 | 958690662 |
28 | 2570501823 |
29 | 6906337888 |
30 | 18589047554 |
[0,0,4,6,4,16,46,84,224,558,1380,3418,9272,23340, 58462,153503,404026,1041448,2725482,7226277, 19073734,50488500,134468292,358721980,958690662, 2570501823,6906337888,18589047554] |