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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 13 |
| 2 | 113 |
| 3 | 909 |
| 4 | 7169 |
| 5 | 56237 |
| 6 | 440497 |
| 7 | 3448941 |
| 8 | 27000961 |
| 9 | 211377613 |
| 10 | 1654759793 |
| 11 | 12954178509 |
| 12 | 101410868609 |
| 13 | 793887651437 |
| 14 | 6214891748017 |
| 15 | 48652827405741 |
| 16 | 380875114341121 |
| 17 | 2981653077513613 |
| 18 | 23341653831337073 |
| 19 | 182728435995639309 |
[1,13,113,909,7169,56237,440497,3448941,27000961, 211377613,1654759793,12954178509,101410868609, 793887651437,6214891748017,48652827405741, 380875114341121,2981653077513613, 23341653831337073,182728435995639309] |