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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 66 |
| 3 | 497 |
| 4 | 3808 |
| 5 | 29212 |
| 6 | 223995 |
| 7 | 1717882 |
| 8 | 13174266 |
| 9 | 101033369 |
| 10 | 774822892 |
| 11 | 5942100272 |
| 12 | 45569854023 |
| 13 | 349474289622 |
| 14 | 2680111429330 |
| 15 | 20553721242845 |
| 16 | 157626080234992 |
| 17 | 1208831279237072 |
| 18 | 9270503076704855 |
| 19 | 71095304015354510 |
[7,66,497,3808,29212,223995,1717882,13174266, 101033369,774822892,5942100272,45569854023, 349474289622,2680111429330,20553721242845, 157626080234992,1208831279237072,9270503076704855, 71095304015354510] |