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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 11 |
| 3 | 34 |
| 4 | 191 |
| 5 | 546 |
| 6 | 4067 |
| 7 | 17412 |
| 8 | 112660 |
| 9 | 634311 |
| 10 | 3789374 |
| 11 | 21768434 |
| 12 | 127922510 |
| 13 | 740390307 |
| 14 | 4332789535 |
| 15 | 25223205362 |
| 16 | 147301185909 |
| 17 | 859118123084 |
| 18 | 5015850403762 |
| 19 | 29268855094463 |
| 20 | 170854627899949 |
| 21 | 997148101828012 |
[21,11,34,191,546,4067,17412,112660,634311, 3789374,21768434,127922510,740390307,4332789535, 25223205362,147301185909,859118123084, 5015850403762,29268855094463,170854627899949, 997148101828012] |