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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 18 |
| 2 | 123 |
| 3 | 843 |
| 4 | 5778 |
| 5 | 39603 |
| 6 | 271443 |
| 7 | 1860498 |
| 8 | 12752043 |
| 9 | 87403803 |
| 10 | 599074578 |
| 11 | 4106118243 |
| 12 | 28143753123 |
| 13 | 192900153618 |
| 14 | 1322157322203 |
| 15 | 9062201101803 |
| 16 | 62113250390418 |
| 17 | 425730551631123 |
| 18 | 2918000611027443 |
| 19 | 20000273725560978 |
| 20 | 137083915467899403 |
| 21 | 939587134549734843 |
[3,18,123,843,5778,39603,271443,1860498,12752043, 87403803,599074578,4106118243,28143753123, 192900153618,1322157322203,9062201101803, 62113250390418,425730551631123,2918000611027443, 20000273725560978,137083915467899403, 939587134549734843] |