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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 16 |
| 5 | 37 |
| 6 | 86 |
| 7 | 199 |
| 8 | 456 |
| 9 | 1033 |
| 10 | 2314 |
| 11 | 5131 |
| 12 | 11276 |
| 13 | 24589 |
| 14 | 53262 |
| 15 | 114703 |
| 16 | 245776 |
| 17 | 524305 |
| 18 | 1114130 |
| 19 | 2359315 |
| 20 | 4980756 |
| 21 | 10485781 |
| 22 | 22020118 |
| 23 | 46137367 |
| 24 | 96469016 |
| 25 | 201326617 |
| 26 | 419430426 |
| 27 | 872415259 |
| 28 | 1811939356 |
| 29 | 3758096413 |
[1,3,7,16,37,86,199,456,1033,2314,5131,11276, 24589,53262,114703,245776,524305,1114130,2359315, 4980756,10485781,22020118,46137367,96469016, 201326617,419430426,872415259,1811939356, 3758096413] |