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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 7 |
| 5 | 14 |
| 6 | 27 |
| 7 | 53 |
| 8 | 104 |
| 9 | 208 |
| 10 | 415 |
| 11 | 836 |
| 12 | 1690 |
| 13 | 3434 |
| 14 | 7004 |
| 15 | 14342 |
| 16 | 29460 |
| 17 | 60707 |
| 18 | 125443 |
| 19 | 259883 |
| 20 | 539689 |
| 21 | 1123226 |
| 22 | 2342493 |
| 23 | 4894590 |
| 24 | 10245321 |
| 25 | 21481047 |
| 26 | 45108768 |
| 27 | 94863801 |
| 28 | 199772929 |
| 29 | 421245065 |
| 30 | 889331420 |
| 31 | 1879723964 |
| 32 | 3977402460 |
| 33 | 8424718846 |
[1,1,2,4,7,14,27,53,104,208,415,836,1690,3434, 7004,14342,29460,60707,125443,259883,539689, 1123226,2342493,4894590,10245321,21481047, 45108768,94863801,199772929,421245065,889331420, 1879723964,3977402460,8424718846] |