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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 44 |
| 4 | 401 |
| 5 | 4682 |
| 6 | 66431 |
| 7 | 1111112 |
| 8 | 21435889 |
| 9 | 469070942 |
| 10 | 11488207655 |
| 11 | 311505013052 |
| 12 | 9267595563617 |
| 13 | 300239975158034 |
| 14 | 10523614159962559 |
| 15 | 396861212733968144 |
| 16 | 16024522975978953761 |
| 17 | 689852631578947368422 |
| 18 | 31544039619835776489479 |
[1,2,7,44,401,4682,66431,1111112,21435889, 469070942,11488207655,311505013052,9267595563617, 300239975158034,10523614159962559, 396861212733968144,16024522975978953761, 689852631578947368422,31544039619835776489479] |