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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 2 |
| 6 | 3 |
| 7 | 6 |
| 8 | 7 |
| 9 | 12 |
| 10 | 19 |
| 11 | 32 |
| 12 | 53 |
| 13 | 90 |
| 14 | 156 |
| 15 | 276 |
| 16 | 493 |
| 17 | 878 |
| 18 | 1566 |
| 19 | 2834 |
| 20 | 5146 |
| 21 | 9396 |
| 22 | 17358 |
| 23 | 32042 |
| 24 | 59434 |
| 25 | 110292 |
| 26 | 204332 |
| 27 | 380548 |
| 28 | 713601 |
| 29 | 1342448 |
| 30 | 2538012 |
| 31 | 4808578 |
| 32 | 9043605 |
| 33 | 17070234 |
| 34 | 32268611 |
| 35 | 61271738 |
| 36 | 116123939 |
| 37 | 220993892 |
| 38 | 421000142 |
| 39 | 802844420 |
| 40 | 1534312896 |
[1,1,1,2,2,2,3,6,7,12,19,32,53,90,156,276,493,878, 1566,2834,5146,9396,17358,32042,59434,110292, 204332,380548,713601,1342448,2538012,4808578, 9043605,17070234,32268611,61271738,116123939, 220993892,421000142,802844420,1534312896] |