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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 23 |
| 4 | 193 |
| 5 | 2133 |
| 6 | 29410 |
| 7 | 486602 |
| 8 | 9395315 |
| 9 | 207341153 |
| 10 | 5147194204 |
| 11 | 141939786588 |
| 12 | 4304047703755 |
| 13 | 142317774817901 |
| 14 | 5095781837539766 |
| 15 | 196403997108015332 |
| 16 | 8106948166404074281 |
| 17 | 356781439557643998591 |
| 18 | 16675999433772328981216 |
| 19 | 824952192369049982670686 |
[1,1,4,23,193,2133,29410,486602,9395315,207341153, 5147194204,141939786588,4304047703755, 142317774817901,5095781837539766, 196403997108015332,8106948166404074281, 356781439557643998591,16675999433772328981216, 824952192369049982670686] |