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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 11 |
| 2 | 76 |
| 3 | 425 |
| 4 | 2109 |
| 5 | 9709 |
| 6 | 42504 |
| 7 | 179630 |
| 8 | 740025 |
| 9 | 2991495 |
| 10 | 11920740 |
| 11 | 46981740 |
| 12 | 183579396 |
| 13 | 712493461 |
| 14 | 2750450981 |
| 15 | 10572046555 |
| 16 | 40495806764 |
| 17 | 154683305139 |
| 18 | 589504177384 |
| 19 | 2242448706435 |
| 20 | 8517201473375 |
| 21 | 32309383853565 |
[1,11,76,425,2109,9709,42504,179630,740025, 2991495,11920740,46981740,183579396,712493461, 2750450981,10572046555,40495806764,154683305139, 589504177384,2242448706435,8517201473375, 32309383853565] |