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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 7 |
| 3 | 19 |
| 4 | 45 |
| 5 | 101 |
| 6 | 215 |
| 7 | 447 |
| 8 | 913 |
| 9 | 1849 |
| 10 | 3727 |
| 11 | 7485 |
| 12 | 15007 |
| 13 | 30055 |
| 14 | 60153 |
| 15 | 120353 |
| 16 | 240759 |
| 17 | 481577 |
| 18 | 963215 |
| 19 | 1926497 |
| 20 | 3853065 |
| 21 | 7706203 |
| 22 | 15412485 |
| 23 | 30825053 |
| 24 | 61650195 |
| 25 | 123300487 |
| 26 | 246601075 |
| 27 | 493202253 |
| 28 | 986404613 |
| 29 | 1972809335 |
| 30 | 3945618783 |
| 31 | 7891237693 |
| 32 | 15782475517 |
[2,7,19,45,101,215,447,913,1849,3727,7485,15007, 30055,60153,120353,240759,481577,963215,1926497, 3853065,7706203,15412485,30825053,61650195, 123300487,246601075,493202253,986404613, 1972809335,3945618783,7891237693,15782475517] |