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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 35 |
| 3 | 160 |
| 4 | 660 |
| 5 | 2651 |
| 6 | 10350 |
| 7 | 39807 |
| 8 | 151463 |
| 9 | 572454 |
| 10 | 2153977 |
| 11 | 8081566 |
| 12 | 30264786 |
| 13 | 113201857 |
| 14 | 423085492 |
| 15 | 1580453125 |
| 16 | 5901900685 |
| 17 | 22034817900 |
| 18 | 82255893847 |
| 19 | 307033492332 |
| 20 | 1145986101448 |
| 21 | 4277171754383 |
| 22 | 15963330711354 |
| 23 | 59577671664211 |
[8,35,160,660,2651,10350,39807,151463,572454, 2153977,8081566,30264786,113201857,423085492, 1580453125,5901900685,22034817900,82255893847, 307033492332,1145986101448,4277171754383, 15963330711354,59577671664211] |