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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 14 |
| 6 | 45 |
| 7 | 165 |
| 8 | 614 |
| 9 | 2420 |
| 10 | 9782 |
| 11 | 40721 |
| 12 | 172854 |
| 13 | 747625 |
| 14 | 3281033 |
| 15 | 14588999 |
| 16 | 65592358 |
| 17 | 297820064 |
| 18 | 1363972446 |
| 19 | 6295216621 |
| 20 | 29256113070 |
| 21 | 136814371958 |
| 22 | 643430589703 |
| 23 | 3041643631339 |
| 24 | 14446433252944 |
| 25 | 68911476411569 |
| 26 | 330030134676707 |
| 27 | 1586412426225015 |
| 28 | 7651783461702750 |
| 29 | 37024499137803700 |
[0,1,1,2,4,14,45,165,614,2420,9782,40721,172854, 747625,3281033,14588999,65592358,297820064, 1363972446,6295216621,29256113070,136814371958, 643430589703,3041643631339,14446433252944, 68911476411569,330030134676707,1586412426225015, 7651783461702750,37024499137803700] |