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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 5 |
| 6 | 10 |
| 7 | 20 |
| 8 | 38 |
| 9 | 74 |
| 10 | 146 |
| 11 | 294 |
| 12 | 586 |
| 13 | 1172 |
| 14 | 2344 |
| 15 | 4684 |
| 16 | 9364 |
| 17 | 18724 |
| 18 | 37452 |
| 19 | 74900 |
| 20 | 149800 |
| 21 | 299600 |
| 22 | 599192 |
| 23 | 1198376 |
| 24 | 2396744 |
| 25 | 4793496 |
| 26 | 9586984 |
| 27 | 19173968 |
| 28 | 38347936 |
| 29 | 76695856 |
| 30 | 153391696 |
| 31 | 306783376 |
| 32 | 613566768 |
| 33 | 1227133520 |
| 34 | 2454267040 |
[1,1,1,1,3,5,10,20,38,74,146,294,586,1172,2344, 4684,9364,18724,37452,74900,149800,299600,599192, 1198376,2396744,4793496,9586984,19173968,38347936, 76695856,153391696,306783376,613566768,1227133520, 2454267040] |