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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 13 |
| 3 | 63 |
| 4 | 313 |
| 5 | 1563 |
| 6 | 7813 |
| 7 | 39063 |
| 8 | 195313 |
| 9 | 976563 |
| 10 | 4882813 |
| 11 | 24414063 |
| 12 | 122070313 |
| 13 | 610351563 |
| 14 | 3051757813 |
| 15 | 15258789063 |
| 16 | 76293945313 |
| 17 | 381469726563 |
| 18 | 1907348632813 |
| 19 | 9536743164063 |
| 20 | 47683715820313 |
| 21 | 238418579101563 |
[1,3,13,63,313,1563,7813,39063,195313,976563, 4882813,24414063,122070313,610351563,3051757813, 15258789063,76293945313,381469726563, 1907348632813,9536743164063,47683715820313, 238418579101563] |