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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 25 |
| 4 | 109 |
| 5 | 445 |
| 6 | 2041 |
| 7 | 8903 |
| 8 | 41777 |
| 9 | 188835 |
| 10 | 898187 |
| 11 | 4149843 |
| 12 | 19910578 |
| 13 | 93363307 |
| 14 | 450660409 |
| 15 | 2135553110 |
| 16 | 10354383193 |
| 17 | 49450864210 |
| 18 | 240592458544 |
| 19 | 1155935532779 |
| 20 | 5639339702694 |
| 21 | 27222773812905 |
| 22 | 133104616214822 |
| 23 | 644989013091962 |
| 24 | 3159480561138418 |
| 25 | 15357981391532350 |
| 26 | 75348649206675611 |
[1,2,7,25,109,445,2041,8903,41777,188835,898187, 4149843,19910578,93363307,450660409,2135553110, 10354383193,49450864210,240592458544, 1155935532779,5639339702694,27222773812905, 133104616214822,644989013091962,3159480561138418, 15357981391532350,75348649206675611] |