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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 14 |
| 5 | 38 |
| 6 | 96 |
| 7 | 254 |
| 8 | 656 |
| 9 | 1724 |
| 10 | 4492 |
| 11 | 11776 |
| 12 | 30774 |
| 13 | 80608 |
| 14 | 210892 |
| 15 | 552226 |
| 16 | 1445374 |
| 17 | 3784308 |
| 18 | 9906482 |
| 19 | 25936206 |
| 20 | 67899344 |
| 21 | 177764618 |
| 22 | 465387226 |
| 23 | 1218404344 |
| 24 | 3189806746 |
| 25 | 8351034954 |
| 26 | 21863248282 |
| 27 | 57238759726 |
| 28 | 149852900454 |
| 29 | 392320072078 |
| 30 | 1027106974446 |
| 31 | 2689001192594 |
| 32 | 7039895709776 |
[1,2,6,14,38,96,254,656,1724,4492,11776,30774, 80608,210892,552226,1445374,3784308,9906482, 25936206,67899344,177764618,465387226,1218404344, 3189806746,8351034954,21863248282,57238759726, 149852900454,392320072078,1027106974446, 2689001192594,7039895709776] |