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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 12 |
| 4 | 64 |
| 5 | 388 |
| 6 | 2547 |
| 7 | 17675 |
| 8 | 127930 |
| 9 | 957361 |
| 10 | 7363756 |
| 11 | 57974777 |
| 12 | 465801960 |
| 13 | 3811089824 |
| 14 | 31703423654 |
| 15 | 267851394004 |
| 16 | 2296630925851 |
| 17 | 19975895528930 |
| 18 | 176220976812512 |
| 19 | 1576741746108772 |
| 20 | 14312547251073466 |
| 21 | 131857909192636473 |
| 22 | 1233606830533043503 |
| 23 | 11728329063674693906 |
| 24 | 113406667874700311312 |
| 25 | 1116271813812969589106 |
| 26 | 11195131545541254173944 |
[1,1,3,12,64,388,2547,17675,127930,957361,7363756, 57974777,465801960,3811089824,31703423654, 267851394004,2296630925851,19975895528930, 176220976812512,1576741746108772, 14312547251073466,131857909192636473, 1233606830533043503,11728329063674693906, 113406667874700311312,1116271813812969589106, 11195131545541254173944] |