n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 1 |
4 | 4 |
5 | 31 |
6 | 146 |
7 | 1289 |
8 | 7736 |
9 | 68811 |
10 | 354568 |
11 | 2562282 |
12 | 12614090 |
13 | 80560052 |
14 | 406847624 |
15 | 2530379183 |
16 | 13576171696 |
17 | 85562497735 |
18 | 476311791218 |
19 | 2983359368303 |
20 | 16861046247216 |
21 | 104017882519889 |
22 | 591843352618090 |
23 | 3599197579892399 |
[0,0,1,4,31,146,1289,7736,68811,354568,2562282, 12614090,80560052,406847624,2530379183, 13576171696,85562497735,476311791218, 2983359368303,16861046247216,104017882519889, 591843352618090,3599197579892399] |