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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 217 |
| 5 | 2667 |
| 6 | 31 |
| 7 | 889 |
| 8 | 27559 |
| 9 | 3937 |
| 10 | 172011 |
| 11 | 677207307 |
| 12 | 127 |
| 13 | 1777447 |
| 14 | 225735769 |
| 15 | 57337 |
| 16 | 11010027 |
| 17 | 12189603 |
| 18 | 3612185689 |
| 19 | 698915267211 |
| 20 | 253921 |
| 21 | 113770279 |
| 22 | 116522119 |
| 23 | 29587412978599 |
| 24 | 917497 |
| 25 | 1040257 |
| 26 | 931892355289 |
| 27 | 954432676729 |
| 28 | 811637999283747 |
[1,3,7,217,2667,31,889,27559,3937,172011, 677207307,127,1777447,225735769,57337,11010027, 12189603,3612185689,698915267211,253921,113770279, 116522119,29587412978599,917497,1040257, 931892355289,954432676729,811637999283747] |