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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 6 |
| 5 | 12 |
| 6 | 22 |
| 7 | 40 |
| 8 | 74 |
| 9 | 136 |
| 10 | 250 |
| 11 | 460 |
| 12 | 846 |
| 13 | 1556 |
| 14 | 2862 |
| 15 | 5264 |
| 16 | 9682 |
| 17 | 17808 |
| 18 | 32754 |
| 19 | 60244 |
| 20 | 110806 |
| 21 | 203804 |
| 22 | 374854 |
| 23 | 689464 |
| 24 | 1268122 |
| 25 | 2332440 |
| 26 | 4290026 |
| 27 | 7890588 |
| 28 | 14513054 |
| 29 | 26693668 |
| 30 | 49097310 |
| 31 | 90304032 |
| 32 | 166095010 |
| 33 | 305496352 |
| 34 | 561895394 |
[1,2,4,6,12,22,40,74,136,250,460,846,1556,2862, 5264,9682,17808,32754,60244,110806,203804,374854, 689464,1268122,2332440,4290026,7890588,14513054, 26693668,49097310,90304032,166095010,305496352, 561895394] |