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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 299 |
| 3 | 3879 |
| 4 | 52199 |
| 5 | 700972 |
| 6 | 9388654 |
| 7 | 125887202 |
| 8 | 1687776548 |
| 9 | 22627774940 |
| 10 | 303374187415 |
| 11 | 4067381827553 |
| 12 | 54531991863699 |
| 13 | 731118983022104 |
| 14 | 9802227619735676 |
| 15 | 131420017672187029 |
| 16 | 1761969037670761907 |
[21,299,3879,52199,700972,9388654,125887202, 1687776548,22627774940,303374187415,4067381827553, 54531991863699,731118983022104,9802227619735676, 131420017672187029,1761969037670761907] |