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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 33 |
| 5 | 157 |
| 6 | 1077 |
| 7 | 12562 |
| 8 | 276361 |
| 9 | 12023304 |
| 10 | 1019341931 |
| 11 | 165104554019 |
| 12 | 50503104222056 |
| 13 | 29054325051128443 |
| 14 | 31426537149908636858 |
| 15 | 64001044963441537716700 |
| 16 | 245935895697060179316310623 |
| 17 | 1787577789272803153324620542087 |
| 18 | 24637809499317378365431171138790458 |
[1,1,3,9,33,157,1077,12562,276361,12023304, 1019341931,165104554019,50503104222056, 29054325051128443,31426537149908636858, 64001044963441537716700, 245935895697060179316310623, 1787577789272803153324620542087, 24637809499317378365431171138790458] |