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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 16 |
| 6 | 34 |
| 7 | 71 |
| 8 | 153 |
| 9 | 332 |
| 10 | 730 |
| 11 | 1617 |
| 12 | 3620 |
| 13 | 8148 |
| 14 | 18473 |
| 15 | 42097 |
| 16 | 96420 |
| 17 | 221770 |
| 18 | 512133 |
| 19 | 1186712 |
| 20 | 2758707 |
| 21 | 6431395 |
| 22 | 15033320 |
| 23 | 35224825 |
| 24 | 82720273 |
| 25 | 194655030 |
| 26 | 458931973 |
| 27 | 1083926784 |
| 28 | 2564305754 |
| 29 | 6075896220 |
| 30 | 14417163975 |
| 31 | 34256236039 |
| 32 | 81499535281 |
| 33 | 194130771581 |
[1,1,2,4,8,16,34,71,153,332,730,1617,3620,8148, 18473,42097,96420,221770,512133,1186712,2758707, 6431395,15033320,35224825,82720273,194655030, 458931973,1083926784,2564305754,6075896220, 14417163975,34256236039,81499535281,194130771581] |