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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 49 |
| 5 | 177 |
| 6 | 645 |
| 7 | 2489 |
| 8 | 9621 |
| 9 | 37389 |
| 10 | 149641 |
| 11 | 595069 |
| 12 | 2401449 |
| 13 | 9767733 |
| 14 | 39781097 |
| 15 | 163511229 |
| 16 | 674229217 |
| 17 | 2789228345 |
| 18 | 11601713781 |
| 19 | 48355166633 |
| 20 | 202230993541 |
| 21 | 848452552753 |
| 22 | 3566524103253 |
| 23 | 15033723662041 |
| 24 | 63503474794893 |
| 25 | 268735010971945 |
| 26 | 1139627242648765 |
| 27 | 4840572436506129 |
[1,1,5,13,49,177,645,2489,9621,37389,149641, 595069,2401449,9767733,39781097,163511229, 674229217,2789228345,11601713781,48355166633, 202230993541,848452552753,3566524103253, 15033723662041,63503474794893,268735010971945, 1139627242648765,4840572436506129] |