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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 18 |
| 6 | 36 |
| 7 | 72 |
| 8 | 145 |
| 9 | 290 |
| 10 | 580 |
| 11 | 1161 |
| 12 | 2322 |
| 13 | 4644 |
| 14 | 9288 |
| 15 | 18576 |
| 16 | 37153 |
| 17 | 74306 |
| 18 | 148612 |
| 19 | 297225 |
| 20 | 594450 |
| 21 | 1188900 |
| 22 | 2377800 |
| 23 | 4755601 |
| 24 | 9511202 |
| 25 | 19022404 |
| 26 | 38044809 |
| 27 | 76089618 |
| 28 | 152179236 |
| 29 | 304358472 |
| 30 | 608716944 |
| 31 | 1217433888 |
| 32 | 2434867777 |
| 33 | 4869735554 |
| 34 | 9739471108 |
[1,2,4,9,18,36,72,145,290,580,1161,2322,4644,9288, 18576,37153,74306,148612,297225,594450,1188900, 2377800,4755601,9511202,19022404,38044809, 76089618,152179236,304358472,608716944,1217433888, 2434867777,4869735554,9739471108] |