n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 0 |
4 | 0 |
5 | 2 |
6 | 9 |
7 | 50 |
8 | 206 |
9 | 862 |
10 | 3384 |
11 | 13250 |
12 | 50852 |
13 | 194810 |
14 | 741884 |
15 | 2823712 |
16 | 10735998 |
17 | 40843370 |
18 | 155483873 |
19 | 592614050 |
20 | 2261585918 |
21 | 8643288808 |
22 | 33080772468 |
23 | 126797503250 |
24 | 486710415710 |
25 | 1870851589552 |
26 | 7201012694120 |
27 | 27752927349880 |
28 | 107092389688830 |
29 | 413729680838330 |
[0,0,0,0,2,9,50,206,862,3384,13250,50852,194810, 741884,2823712,10735998,40843370,155483873, 592614050,2261585918,8643288808,33080772468, 126797503250,486710415710,1870851589552, 7201012694120,27752927349880,107092389688830, 413729680838330] |