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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 12 |
| 4 | 27 |
| 5 | 54 |
| 6 | 112 |
| 7 | 224 |
| 8 | 453 |
| 9 | 906 |
| 10 | 1818 |
| 11 | 3636 |
| 12 | 7279 |
| 13 | 14558 |
| 14 | 29124 |
| 15 | 58248 |
| 16 | 116505 |
| 17 | 233010 |
| 18 | 466030 |
| 19 | 932060 |
| 20 | 1864131 |
| 21 | 3728262 |
| 22 | 7456536 |
| 23 | 14913072 |
| 24 | 29826157 |
| 25 | 59652314 |
| 26 | 119304642 |
| 27 | 238609284 |
| 28 | 477218583 |
| 29 | 954437166 |
| 30 | 1908874348 |
| 31 | 3817748696 |
[1,2,6,12,27,54,112,224,453,906,1818,3636,7279, 14558,29124,58248,116505,233010,466030,932060, 1864131,3728262,7456536,14913072,29826157, 59652314,119304642,238609284,477218583,954437166, 1908874348,3817748696] |