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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 7 |
| 5 | 13 |
| 6 | 28 |
| 7 | 55 |
| 8 | 109 |
| 9 | 220 |
| 10 | 439 |
| 11 | 877 |
| 12 | 1756 |
| 13 | 3511 |
| 14 | 7021 |
| 15 | 14044 |
| 16 | 28087 |
| 17 | 56173 |
| 18 | 112348 |
| 19 | 224695 |
| 20 | 449389 |
| 21 | 898780 |
| 22 | 1797559 |
| 23 | 3595117 |
| 24 | 7190236 |
| 25 | 14380471 |
| 26 | 28760941 |
| 27 | 57521884 |
| 28 | 115043767 |
| 29 | 230087533 |
| 30 | 460175068 |
| 31 | 920350135 |
| 32 | 1840700269 |
| 33 | 3681400540 |
[1,1,1,4,7,13,28,55,109,220,439,877,1756,3511, 7021,14044,28087,56173,112348,224695,449389, 898780,1797559,3595117,7190236,14380471,28760941, 57521884,115043767,230087533,460175068,920350135, 1840700269,3681400540] |