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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 7 |
| 3 | 73 |
| 4 | 1117 |
| 5 | 22741 |
| 6 | 580159 |
| 7 | 17826985 |
| 8 | 641494249 |
| 9 | 26473635865 |
| 10 | 1232945359111 |
| 11 | 63978649829161 |
| 12 | 3660871368065509 |
| 13 | 229016870623703917 |
| 14 | 15550838554432967647 |
| 15 | 1139139301403727884521 |
| 16 | 89544381521098908259729 |
| 17 | 7518611017848248249471089 |
[1,1,7,73,1117,22741,580159,17826985,641494249, 26473635865,1232945359111,63978649829161, 3660871368065509,229016870623703917, 15550838554432967647,1139139301403727884521, 89544381521098908259729,7518611017848248249471089] |