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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 9 |
| 4 | 19 |
| 5 | 41 |
| 6 | 87 |
| 7 | 185 |
| 8 | 391 |
| 9 | 825 |
| 10 | 1735 |
| 11 | 3641 |
| 12 | 7623 |
| 13 | 15929 |
| 14 | 33223 |
| 15 | 69177 |
| 16 | 143815 |
| 17 | 298553 |
| 18 | 618951 |
| 19 | 1281593 |
| 20 | 2650567 |
| 21 | 5475897 |
| 22 | 11301319 |
| 23 | 23301689 |
| 24 | 48001479 |
| 25 | 98799161 |
| 26 | 203190727 |
| 27 | 417566265 |
| 28 | 857502151 |
| 29 | 1759743545 |
| 30 | 3608965575 |
[1,2,4,9,19,41,87,185,391,825,1735,3641,7623, 15929,33223,69177,143815,298553,618951,1281593, 2650567,5475897,11301319,23301689,48001479, 98799161,203190727,417566265,857502151,1759743545, 3608965575] |