n | a(n) |
---|---|
0 | 1 |
1 | 0 |
2 | 0 |
3 | 1 |
4 | 0 |
5 | 3 |
6 | 2 |
7 | 12 |
8 | 18 |
9 | 65 |
10 | 138 |
11 | 432 |
12 | 1074 |
13 | 3231 |
14 | 8718 |
15 | 25999 |
16 | 73650 |
17 | 220215 |
18 | 643546 |
19 | 1937877 |
20 | 5783700 |
21 | 17564727 |
22 | 53222094 |
23 | 163009086 |
24 | 499634508 |
25 | 1542392088 |
26 | 4770925446 |
27 | 14832934031 |
28 | 46227584010 |
29 | 144632622552 |
30 | 453628244950 |
[1,0,0,1,0,3,2,12,18,65,138,432,1074,3231,8718, 25999,73650,220215,643546,1937877,5783700, 17564727,53222094,163009086,499634508,1542392088, 4770925446,14832934031,46227584010,144632622552, 453628244950] |