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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | 51 |
| 3 | 651 |
| 4 | 13131 |
| 5 | 435801 |
| 6 | 24530016 |
| 7 | 2394413286 |
| 8 | 412135908606 |
| 9 | 126722253316281 |
| 10 | 70336222713070656 |
| 11 | 71088278975389204986 |
| 12 | 131802456226253519662956 |
| 13 | 451158681817567800972000111 |
[1,6,51,651,13131,435801,24530016,2394413286, 412135908606,126722253316281,70336222713070656, 71088278975389204986,131802456226253519662956, 451158681817567800972000111] |