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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 10 |
| 4 | 213 |
| 5 | 2292 |
| 6 | 21762 |
| 7 | 184076 |
| 8 | 1457827 |
| 9 | 11000888 |
| 10 | 80107879 |
| 11 | 567420546 |
| 12 | 3931417538 |
| 13 | 26752272278 |
| 14 | 179329108005 |
| 15 | 1186930999936 |
| 16 | 7770945222145 |
| 17 | 50399529101088 |
| 18 | 324186782002754 |
| 19 | 2070149445768880 |
| 20 | 13133990417566391 |
[0,1,10,213,2292,21762,184076,1457827,11000888, 80107879,567420546,3931417538,26752272278, 179329108005,1186930999936,7770945222145, 50399529101088,324186782002754,2070149445768880, 13133990417566391] |