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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 3 |
| 4 | 5 |
| 5 | 9 |
| 6 | 15 |
| 7 | 26 |
| 8 | 46 |
| 9 | 82 |
| 10 | 147 |
| 11 | 268 |
| 12 | 492 |
| 13 | 909 |
| 14 | 1688 |
| 15 | 3151 |
| 16 | 5909 |
| 17 | 11123 |
| 18 | 21010 |
| 19 | 39809 |
| 20 | 75638 |
| 21 | 144073 |
| 22 | 275050 |
| 23 | 526182 |
| 24 | 1008516 |
| 25 | 1936352 |
| 26 | 3723754 |
| 27 | 7171675 |
| 28 | 13831089 |
| 29 | 26708310 |
| 30 | 51636066 |
| 31 | 99940774 |
| 32 | 193635250 |
| 33 | 375535031 |
| 34 | 728979766 |
| 35 | 1416303547 |
[2,2,3,5,9,15,26,46,82,147,268,492,909,1688,3151, 5909,11123,21010,39809,75638,144073,275050,526182, 1008516,1936352,3723754,7171675,13831089,26708310, 51636066,99940774,193635250,375535031,728979766, 1416303547] |