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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 19 |
| 5 | 53 |
| 6 | 81 |
| 7 | 823 |
| 8 | 5359 |
| 9 | 12923 |
| 10 | 21877 |
| 11 | 102061 |
| 12 | 354883 |
| 13 | 808865 |
| 14 | 1433689 |
| 15 | 25699639 |
| 16 | 369784999 |
| 17 | 817787423 |
| 18 | 1487830821 |
| 19 | 6512750579 |
| 20 | 23917578595 |
| 21 | 51908057021 |
| 22 | 96040578001 |
| 23 | 827937066989 |
| 24 | 6166467806391 |
| 25 | 13211837015707 |
[1,1,7,19,53,81,823,5359,12923,21877,102061, 354883,808865,1433689,25699639,369784999, 817787423,1487830821,6512750579,23917578595, 51908057021,96040578001,827937066989, 6166467806391,13211837015707] |