n | a(n) |
---|---|
3 | 0 |
4 | 0 |
5 | 4 |
6 | 2 |
7 | 5 |
8 | 21 |
9 | 42 |
10 | 88 |
11 | 261 |
12 | 592 |
13 | 1384 |
14 | 3656 |
15 | 8815 |
16 | 21561 |
17 | 55669 |
18 | 140789 |
19 | 357647 |
20 | 925262 |
21 | 2401128 |
22 | 6262335 |
23 | 16412670 |
24 | 43201778 |
25 | 114204540 |
26 | 302442977 |
27 | 802726911 |
28 | 2136397918 |
29 | 5694213070 |
30 | 15199124391 |
31 | 40644374977 |
[0,0,4,2,5,21,42,88,261,592,1384,3656,8815,21561, 55669,140789,357647,925262,2401128,6262335, 16412670,43201778,114204540,302442977,802726911, 2136397918,5694213070,15199124391,40644374977] |