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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 9 |
| 4 | 11 |
| 5 | 20 |
| 6 | 691 |
| 7 | 711 |
| 8 | 1402 |
| 9 | 6319 |
| 10 | 7721 |
| 11 | 14040 |
| 12 | 485081 |
| 13 | 499121 |
| 14 | 984202 |
| 15 | 4435929 |
| 16 | 5420131 |
| 17 | 9856060 |
| 18 | 340526171 |
| 19 | 350382231 |
| 20 | 690908402 |
| 21 | 3114015839 |
| 22 | 3804924241 |
| 23 | 6918940080 |
| 24 | 239048886961 |
| 25 | 245967827041 |
| 26 | 485016714002 |
| 27 | 2186034683049 |
| 28 | 2671051397051 |
[1,1,2,9,11,20,691,711,1402,6319,7721,14040, 485081,499121,984202,4435929,5420131,9856060, 340526171,350382231,690908402,3114015839, 3804924241,6918940080,239048886961,245967827041, 485016714002,2186034683049,2671051397051] |