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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 6 |
| 4 | 11 |
| 5 | 21 |
| 6 | 31 |
| 7 | 55 |
| 8 | 99 |
| 9 | 145 |
| 10 | 252 |
| 11 | 430 |
| 12 | 620 |
| 13 | 1042 |
| 14 | 1786 |
| 15 | 2597 |
| 16 | 4304 |
| 17 | 7241 |
| 18 | 10374 |
| 19 | 17098 |
| 20 | 28967 |
| 21 | 41444 |
| 22 | 68017 |
| 23 | 113746 |
| 24 | 162204 |
| 25 | 268412 |
| 26 | 449318 |
| 27 | 640341 |
| 28 | 1053604 |
| 29 | 1764648 |
| 30 | 2524852 |
| 31 | 4154138 |
| 32 | 6968215 |
| 33 | 9935216 |
| 34 | 16371249 |
| 35 | 27594872 |
| 36 | 39353636 |
| 37 | 64914388 |
| 38 | 109205201 |
[1,2,4,6,11,21,31,55,99,145,252,430,620,1042,1786, 2597,4304,7241,10374,17098,28967,41444,68017, 113746,162204,268412,449318,640341,1053604, 1764648,2524852,4154138,6968215,9935216,16371249, 27594872,39353636,64914388,109205201] |