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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 29 |
| 4 | 139 |
| 5 | 731 |
| 6 | 4096 |
| 7 | 24005 |
| 8 | 145420 |
| 9 | 903503 |
| 10 | 5726290 |
| 11 | 36878978 |
| 12 | 240663403 |
| 13 | 1587928511 |
| 14 | 10575884599 |
| 15 | 71005972250 |
| 16 | 480071241463 |
| 17 | 3265685620913 |
| 18 | 22335284505529 |
| 19 | 153496543690226 |
| 20 | 1059443187603955 |
| 21 | 7340794592800628 |
| 22 | 51042913856490028 |
[1,2,7,29,139,731,4096,24005,145420,903503, 5726290,36878978,240663403,1587928511,10575884599, 71005972250,480071241463,3265685620913, 22335284505529,153496543690226,1059443187603955, 7340794592800628,51042913856490028] |