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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 18 |
| 4 | 194 |
| 5 | 2944 |
| 6 | 57959 |
| 7 | 1398858 |
| 8 | 39981994 |
| 9 | 1320143478 |
| 10 | 49439258516 |
| 11 | 2070409961552 |
| 12 | 95867076538834 |
| 13 | 4863079990663528 |
| 14 | 268198764863998103 |
| 15 | 15977057268090388836 |
| 16 | 1022415045656417706598 |
| 17 | 69946606996018140613292 |
| 18 | 5094427098628436561252367 |
| 19 | 393558075509405403487404506 |
[1,3,18,194,2944,57959,1398858,39981994, 1320143478,49439258516,2070409961552, 95867076538834,4863079990663528, 268198764863998103,15977057268090388836, 1022415045656417706598,69946606996018140613292, 5094427098628436561252367, 393558075509405403487404506] |