n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 0 |
3 | 1 |
4 | 2 |
5 | 4 |
6 | 10 |
7 | 29 |
8 | 90 |
9 | 295 |
10 | 1030 |
11 | 3838 |
12 | 15168 |
13 | 63117 |
14 | 275252 |
15 | 1254801 |
16 | 5968046 |
17 | 29551768 |
18 | 152005634 |
19 | 810518729 |
20 | 4472244574 |
21 | 25497104007 |
22 | 149993156234 |
23 | 909326652914 |
24 | 5674422994544 |
25 | 36408092349897 |
26 | 239942657880360 |
[0,1,0,1,2,4,10,29,90,295,1030,3838,15168,63117, 275252,1254801,5968046,29551768,152005634, 810518729,4472244574,25497104007,149993156234, 909326652914,5674422994544,36408092349897, 239942657880360] |