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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 25 |
| 4 | 102 |
| 5 | 418 |
| 6 | 1822 |
| 7 | 7930 |
| 8 | 35834 |
| 9 | 161326 |
| 10 | 745277 |
| 11 | 3428471 |
| 12 | 16073766 |
| 13 | 75051209 |
| 14 | 355567823 |
| 15 | 1678216641 |
| 16 | 8012934452 |
| 17 | 38128613404 |
| 18 | 183143821040 |
| 19 | 876997842618 |
| 20 | 4232442545636 |
| 21 | 20369705463788 |
| 22 | 98680751392001 |
| 23 | 476873322718406 |
| 24 | 2317449590232091 |
| 25 | 11236950192377100 |
| 26 | 54750669538493457 |
| 27 | 266229930746142702 |
[1,2,7,25,102,418,1822,7930,35834,161326,745277, 3428471,16073766,75051209,355567823,1678216641, 8012934452,38128613404,183143821040,876997842618, 4232442545636,20369705463788,98680751392001, 476873322718406,2317449590232091, 11236950192377100,54750669538493457, 266229930746142702] |