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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 91 |
| 4 | 1210 |
| 5 | 17577 |
| 6 | 270314 |
| 7 | 4326070 |
| 8 | 71300386 |
| 9 | 1202012254 |
| 10 | 20630488004 |
| 11 | 359279348424 |
| 12 | 6332747550808 |
| 13 | 112761701957119 |
| 14 | 2025325557546780 |
| 15 | 36650364776763804 |
| 16 | 667570101840389826 |
| 17 | 12229542931765845994 |
| 18 | 225183117821591853440 |
| 19 | 4165207037639796288385 |
[1,1,8,91,1210,17577,270314,4326070,71300386, 1202012254,20630488004,359279348424,6332747550808, 112761701957119,2025325557546780, 36650364776763804,667570101840389826, 12229542931765845994,225183117821591853440, 4165207037639796288385] |