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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 39 |
| 3 | 321 |
| 4 | 2675 |
| 5 | 22483 |
| 6 | 190345 |
| 7 | 1621413 |
| 8 | 13882947 |
| 9 | 119385663 |
| 10 | 1030434069 |
| 11 | 8921880135 |
| 12 | 77459553549 |
| 13 | 674100041501 |
| 14 | 5878674505303 |
| 15 | 51361306358401 |
| 16 | 449476337521875 |
| 17 | 3939287035681807 |
| 18 | 34570459724919253 |
| 19 | 303749080936528883 |
| 20 | 2671775251987354377 |
| 21 | 23524418982229636185 |
[1,5,39,321,2675,22483,190345,1621413,13882947, 119385663,1030434069,8921880135,77459553549, 674100041501,5878674505303,51361306358401, 449476337521875,3939287035681807, 34570459724919253,303749080936528883, 2671775251987354377,23524418982229636185] |