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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 27 |
| 4 | 115 |
| 5 | 529 |
| 6 | 2369 |
| 7 | 10799 |
| 8 | 50519 |
| 9 | 235731 |
| 10 | 1110857 |
| 11 | 5255015 |
| 12 | 24917719 |
| 13 | 118624427 |
| 14 | 566325889 |
| 15 | 2711707427 |
| 16 | 13018061199 |
| 17 | 62630442305 |
| 18 | 301891809587 |
| 19 | 1457550954737 |
| 20 | 7047249198849 |
| 21 | 34117462763559 |
| 22 | 165364270152729 |
[1,5,27,115,529,2369,10799,50519,235731,1110857, 5255015,24917719,118624427,566325889,2711707427, 13018061199,62630442305,301891809587, 1457550954737,7047249198849,34117462763559, 165364270152729] |