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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 7 |
| 3 | 38 |
| 4 | 192 |
| 5 | 969 |
| 6 | 5115 |
| 7 | 29322 |
| 8 | 187992 |
| 9 | 1370745 |
| 10 | 11392839 |
| 11 | 107043606 |
| 12 | 1122823944 |
| 13 | 12989320785 |
| 14 | 164040593067 |
| 15 | 2243143392138 |
| 16 | 32994768719376 |
| 17 | 519229765892241 |
| 18 | 8701862242296807 |
| 19 | 154700700117472422 |
| 20 | 2907409255935736752 |
| 21 | 57588370882960384377 |
| 22 | 1198954118077558162875 |
[0,1,7,38,192,969,5115,29322,187992,1370745, 11392839,107043606,1122823944,12989320785, 164040593067,2243143392138,32994768719376, 519229765892241,8701862242296807, 154700700117472422,2907409255935736752, 57588370882960384377,1198954118077558162875] |