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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 49 |
| 5 | 321 |
| 6 | 2851 |
| 7 | 24823 |
| 8 | 256257 |
| 9 | 2887489 |
| 10 | 36759331 |
| 11 | 507010791 |
| 12 | 7597222513 |
| 13 | 122184356737 |
| 14 | 2106356007939 |
| 15 | 38693238713431 |
| 16 | 754792977928321 |
| 17 | 15572911248409473 |
| 18 | 338800604611562947 |
| 19 | 7749991799652960199 |
| 20 | 185934065196259734321 |
| 21 | 4667877395135551746241 |
[1,1,3,7,49,321,2851,24823,256257,2887489, 36759331,507010791,7597222513,122184356737, 2106356007939,38693238713431,754792977928321, 15572911248409473,338800604611562947, 7749991799652960199,185934065196259734321, 4667877395135551746241] |