n | a(n) |
---|---|
3 | 4 |
4 | 0 |
5 | 0 |
6 | 4 |
7 | 28 |
8 | 80 |
9 | 120 |
10 | 120 |
11 | 264 |
12 | 1080 |
13 | 3120 |
14 | 6440 |
15 | 11960 |
16 | 26688 |
17 | 70448 |
18 | 179340 |
19 | 415796 |
20 | 935560 |
21 | 2195536 |
22 | 5374468 |
23 | 13145420 |
24 | 31504224 |
25 | 74955600 |
26 | 180228984 |
27 | 438624648 |
28 | 1069909344 |
29 | 2600077824 |
30 | 6310088640 |
31 | 15363918432 |
[4,0,0,4,28,80,120,120,264,1080,3120,6440,11960, 26688,70448,179340,415796,935560,2195536,5374468, 13145420,31504224,74955600,180228984,438624648, 1069909344,2600077824,6310088640,15363918432] |