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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 74 |
| 4 | 390 |
| 5 | 1801 |
| 6 | 7537 |
| 7 | 29684 |
| 8 | 110796 |
| 9 | 399375 |
| 10 | 1391809 |
| 11 | 4741466 |
| 12 | 15783154 |
| 13 | 51704949 |
| 14 | 166550157 |
| 15 | 530165200 |
| 16 | 1666083296 |
| 17 | 5188200085 |
| 18 | 15993447527 |
| 19 | 48946213794 |
| 20 | 148574713674 |
| 21 | 448343690109 |
| 22 | 1343838723819 |
| 23 | 4008314601988 |
[1,11,74,390,1801,7537,29684,110796,399375, 1391809,4741466,15783154,51704949,166550157, 530165200,1666083296,5188200085,15993447527, 48946213794,148574713674,448343690109, 1343838723819,4008314601988] |