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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 10 |
| 4 | 21 |
| 5 | 44 |
| 6 | 93 |
| 7 | 196 |
| 8 | 411 |
| 9 | 856 |
| 10 | 1771 |
| 11 | 3642 |
| 12 | 7451 |
| 13 | 15178 |
| 14 | 30809 |
| 15 | 62358 |
| 16 | 125921 |
| 17 | 253800 |
| 18 | 510777 |
| 19 | 1026704 |
| 20 | 2061751 |
| 21 | 4137012 |
| 22 | 8295895 |
| 23 | 16627190 |
| 24 | 33311671 |
| 25 | 66716054 |
| 26 | 133582133 |
| 27 | 267407026 |
| 28 | 535206861 |
| 29 | 1071049316 |
| 30 | 2143127061 |
| 31 | 4287918172 |
| 32 | 8578528851 |
| 33 | 17161414288 |
[1,2,5,10,21,44,93,196,411,856,1771,3642,7451, 15178,30809,62358,125921,253800,510777,1026704, 2061751,4137012,8295895,16627190,33311671, 66716054,133582133,267407026,535206861,1071049316, 2143127061,4287918172,8578528851,17161414288] |