| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 59 |
| 5 | 221 |
| 6 | 8807 |
| 7 | 527593 |
| 8 | 52778687 |
| 9 | 113759383 |
| 10 | 13458244873 |
| 11 | 313074529583 |
| 12 | 1434867510253 |
| 13 | 30909266676193 |
| 14 | 842239594152347 |
| 15 | 1075672117707143 |
| 16 | 29204057639975683 |
| 17 | 52376951398984393 |
| 18 | 4785745078256208692917 |
| 19 | 15280437983663153103594943 |
[1,3,13,59,221,8807,527593,52778687,113759383, 13458244873,313074529583,1434867510253, 30909266676193,842239594152347,1075672117707143, 29204057639975683,52376951398984393, 4785745078256208692917,15280437983663153103594943] |