n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 4 |
4 | 0 |
5 | 41 |
6 | 372 |
7 | 3189 |
8 | 15544 |
9 | 94844 |
10 | 606556 |
11 | 3341926 |
12 | 18243164 |
13 | 100641235 |
14 | 541792652 |
15 | 2853058729 |
16 | 14909615644 |
17 | 77215251362 |
18 | 395393899688 |
19 | 2007472847598 |
20 | 10120652405244 |
21 | 50668068245114 |
22 | 252048156500636 |
23 | 1246766824001246 |
24 | 6135236528242698 |
25 | 30045694433419662 |
[0,0,4,0,41,372,3189,15544,94844,606556,3341926, 18243164,100641235,541792652,2853058729, 14909615644,77215251362,395393899688, 2007472847598,10120652405244,50668068245114, 252048156500636,1246766824001246,6135236528242698, 30045694433419662] |