n | a(n) |
---|---|
1 | 1 |
2 | 0 |
3 | 0 |
4 | 0 |
5 | 0 |
6 | 1 |
7 | 3 |
8 | 7 |
9 | 21 |
10 | 57 |
11 | 159 |
12 | 435 |
13 | 1217 |
14 | 3400 |
15 | 9633 |
16 | 27413 |
17 | 78733 |
18 | 227489 |
19 | 661984 |
20 | 1937211 |
21 | 5701733 |
22 | 16865522 |
23 | 50126650 |
24 | 149627241 |
25 | 448448400 |
26 | 1349060262 |
27 | 4072508115 |
28 | 12333762442 |
29 | 37466367898 |
30 | 114133581762 |
[1,0,0,0,0,1,3,7,21,57,159,435,1217,3400,9633, 27413,78733,227489,661984,1937211,5701733, 16865522,50126650,149627241,448448400,1349060262, 4072508115,12333762442,37466367898,114133581762] |