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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 15 |
| 6 | 36 |
| 7 | 85 |
| 8 | 209 |
| 9 | 517 |
| 10 | 1303 |
| 11 | 3312 |
| 12 | 8510 |
| 13 | 22029 |
| 14 | 57447 |
| 15 | 150709 |
| 16 | 397569 |
| 17 | 1053822 |
| 18 | 2805518 |
| 19 | 7498035 |
| 20 | 20110254 |
| 21 | 54110386 |
| 22 | 146021880 |
| 23 | 395114304 |
| 24 | 1071772322 |
| 25 | 2913900196 |
| 26 | 7939004648 |
| 27 | 21672609566 |
| 28 | 59272260791 |
| 29 | 162380575451 |
[1,1,2,3,7,15,36,85,209,517,1303,3312,8510,22029, 57447,150709,397569,1053822,2805518,7498035, 20110254,54110386,146021880,395114304,1071772322, 2913900196,7939004648,21672609566,59272260791, 162380575451] |