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| n | a(n) |
|---|---|
| 1 | 11 |
| 2 | 105 |
| 3 | 923 |
| 4 | 7761 |
| 5 | 63731 |
| 6 | 516825 |
| 7 | 4163723 |
| 8 | 33429921 |
| 9 | 267930851 |
| 10 | 2145445545 |
| 11 | 17171657723 |
| 12 | 137405930481 |
| 13 | 1099379004371 |
| 14 | 8795560934265 |
| 15 | 70366611042923 |
| 16 | 562941406533441 |
| 17 | 4503565396772291 |
| 18 | 36028659967430985 |
| 19 | 288229827558159323 |
| 20 | 2305840813677222801 |
[11,105,923,7761,63731,516825,4163723,33429921, 267930851,2145445545,17171657723,137405930481, 1099379004371,8795560934265,70366611042923, 562941406533441,4503565396772291, 36028659967430985,288229827558159323, 2305840813677222801] |