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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 15 |
| 5 | 85 |
| 6 | 285 |
| 7 | 715 |
| 8 | 1585 |
| 9 | 2285 |
| 10 | 8711 |
| 11 | 28511 |
| 12 | 52515 |
| 13 | 52715 |
| 14 | 72285 |
| 15 | 151285 |
| 16 | 228511 |
| 17 | 285515 |
| 18 | 722211 |
| 19 | 852715 |
| 20 | 878511 |
| 21 | 2858711 |
| 22 | 2878511 |
| 23 | 7182285 |
| 24 | 7182515 |
| 25 | 7271285 |
| 26 | 8785711 |
| 27 | 8877811 |
| 28 | 8881585 |
| 29 | 15878511 |
| 30 | 28551285 |
| 31 | 71782715 |
| 32 | 75582585 |
| 33 | 111887511 |
| 34 | 125585515 |
| 35 | 277881585 |
| 36 | 278852515 |
| 37 | 287275515 |
| 38 | 727157285 |
| 39 | 758785711 |
| 40 | 882185515 |
| 41 | 887285515 |
[1,5,11,15,85,285,715,1585,2285,8711,28511,52515, 52715,72285,151285,228511,285515,722211,852715, 878511,2858711,2878511,7182285,7182515,7271285, 8785711,8877811,8881585,15878511,28551285, 71782715,75582585,111887511,125585515,277881585, 278852515,287275515,727157285,758785711,882185515, 887285515] |