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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 35 |
| 4 | 160 |
| 5 | 752 |
| 6 | 3599 |
| 7 | 17446 |
| 8 | 85376 |
| 9 | 420884 |
| 10 | 2087008 |
| 11 | 10398016 |
| 12 | 52010479 |
| 13 | 261021854 |
| 14 | 1313707256 |
| 15 | 6628095035 |
| 16 | 33512880640 |
| 17 | 169768235840 |
| 18 | 861450392708 |
| 19 | 4377796514152 |
| 20 | 22277498220160 |
| 21 | 113502759811000 |
| 22 | 578931209245760 |
| 23 | 2955873376166144 |
| 24 | 15105883318474991 |
[1,2,8,35,160,752,3599,17446,85376,420884,2087008, 10398016,52010479,261021854,1313707256,6628095035, 33512880640,169768235840,861450392708, 4377796514152,22277498220160,113502759811000, 578931209245760,2955873376166144, 15105883318474991] |