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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 12 |
| 4 | 120 |
| 5 | 1320 |
| 6 | 23100 |
| 7 | 1032300 |
| 8 | 21312000 |
| 9 | 1120212000 |
| 10 | 31311330000 |
| 11 | 2120101110000 |
| 12 | 130203033300000 |
| 13 | 11303022030300000 |
| 14 | 1101030032302200000 |
| 15 | 103001313131311200000 |
[1,1,2,12,120,1320,23100,1032300,21312000, 1120212000,31311330000,2120101110000, 130203033300000,11303022030300000, 1101030032302200000,103001313131311200000] |