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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 12 |
| 5 | 26 |
| 6 | 61 |
| 7 | 134 |
| 8 | 297 |
| 9 | 669 |
| 10 | 1490 |
| 11 | 3321 |
| 12 | 7426 |
| 13 | 16573 |
| 14 | 36986 |
| 15 | 82594 |
| 16 | 184382 |
| 17 | 411599 |
| 18 | 918931 |
| 19 | 2051485 |
| 20 | 4579826 |
| 21 | 10224441 |
| 22 | 22825825 |
| 23 | 50957971 |
| 24 | 113762629 |
| 25 | 253972415 |
| 26 | 566987102 |
| 27 | 1265785592 |
| 28 | 2825836529 |
| 29 | 6308612558 |
| 30 | 14083828826 |
| 31 | 31441815085 |
| 32 | 70193107041 |
| 33 | 156704451838 |
| 34 | 349838982690 |
[1,2,6,12,26,61,134,297,669,1490,3321,7426,16573, 36986,82594,184382,411599,918931,2051485,4579826, 10224441,22825825,50957971,113762629,253972415, 566987102,1265785592,2825836529,6308612558, 14083828826,31441815085,70193107041,156704451838, 349838982690] |