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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 50 |
| 3 | 571 |
| 4 | 6727 |
| 5 | 78800 |
| 6 | 924579 |
| 7 | 10844773 |
| 8 | 127214104 |
| 9 | 1492251709 |
| 10 | 17504551617 |
| 11 | 205333329586 |
| 12 | 2408618523801 |
| 13 | 28253780677867 |
| 14 | 331424891961162 |
| 15 | 3887708335839063 |
| 16 | 45603925604339175 |
| 17 | 534947030615649624 |
[4,50,571,6727,78800,924579,10844773,127214104, 1492251709,17504551617,205333329586,2408618523801, 28253780677867,331424891961162,3887708335839063, 45603925604339175,534947030615649624] |