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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 15 |
| 6 | 30 |
| 7 | 63 |
| 8 | 128 |
| 9 | 252 |
| 10 | 510 |
| 11 | 1012 |
| 12 | 2028 |
| 13 | 4056 |
| 14 | 8120 |
| 15 | 16230 |
| 16 | 32464 |
| 17 | 64923 |
| 18 | 129852 |
| 19 | 259711 |
| 20 | 519420 |
| 21 | 1038828 |
| 22 | 2077658 |
| 23 | 4155318 |
| 24 | 8310648 |
| 25 | 16621300 |
| 26 | 33242586 |
| 27 | 66485178 |
| 28 | 132970348 |
| 29 | 265940701 |
| 30 | 531881400 |
| 31 | 1063762799 |
| 32 | 2127525600 |
[1,2,3,8,15,30,63,128,252,510,1012,2028,4056,8120, 16230,32464,64923,129852,259711,519420,1038828, 2077658,4155318,8310648,16621300,33242586, 66485178,132970348,265940701,531881400,1063762799, 2127525600] |