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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 8 |
| 6 | 16 |
| 7 | 32 |
| 8 | 61 |
| 9 | 115 |
| 10 | 215 |
| 11 | 399 |
| 12 | 738 |
| 13 | 1362 |
| 14 | 2510 |
| 15 | 4622 |
| 16 | 8507 |
| 17 | 15653 |
| 18 | 28797 |
| 19 | 52973 |
| 20 | 97440 |
| 21 | 179228 |
| 22 | 329660 |
| 23 | 606348 |
| 24 | 1115257 |
| 25 | 2051287 |
| 26 | 3772915 |
| 27 | 6939483 |
| 28 | 12763710 |
| 29 | 23476134 |
| 30 | 43179354 |
| 31 | 79419226 |
[1,1,1,4,8,16,32,61,115,215,399,738,1362,2510, 4622,8507,15653,28797,52973,97440,179228,329660, 606348,1115257,2051287,3772915,6939483,12763710, 23476134,43179354,79419226] |