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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 5 |
| 5 | 9 |
| 6 | 15 |
| 7 | 28 |
| 8 | 48 |
| 9 | 90 |
| 10 | 159 |
| 11 | 296 |
| 12 | 537 |
| 13 | 992 |
| 14 | 1830 |
| 15 | 3376 |
| 16 | 6273 |
| 17 | 11609 |
| 18 | 21627 |
| 19 | 40186 |
| 20 | 74966 |
| 21 | 139764 |
| 22 | 261063 |
| 23 | 487901 |
| 24 | 912607 |
| 25 | 1708571 |
| 26 | 3200241 |
| 27 | 5999508 |
| 28 | 11251618 |
| 29 | 21116746 |
| 30 | 39647006 |
| 31 | 74479444 |
| 32 | 139971218 |
| 33 | 263167645 |
| 34 | 494991043 |
[1,1,2,3,5,9,15,28,48,90,159,296,537,992,1830, 3376,6273,11609,21627,40186,74966,139764,261063, 487901,912607,1708571,3200241,5999508,11251618, 21116746,39647006,74479444,139971218,263167645, 494991043] |