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| n | a(n) |
|---|---|
| 10 | 1 |
| 11 | 33 |
| 12 | 630 |
| 13 | 9139 |
| 14 | 111930 |
| 15 | 1221759 |
| 16 | 12271512 |
| 17 | 115775100 |
| 18 | 1040465790 |
| 19 | 8996462475 |
| 20 | 75394027566 |
| 21 | 615790256823 |
| 22 | 4922879481520 |
| 23 | 38650751381832 |
| 24 | 298824321028320 |
| 25 | 2280012686716080 |
| 26 | 17198662594653540 |
| 27 | 128447994798305325 |
[1,33,630,9139,111930,1221759,12271512,115775100, 1040465790,8996462475,75394027566,615790256823, 4922879481520,38650751381832,298824321028320, 2280012686716080,17198662594653540, 128447994798305325] |