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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 11 |
| 6 | 0 |
| 7 | 232 |
| 8 | 2295 |
| 9 | 26714 |
| 10 | 453871 |
| 11 | 7053157 |
| 12 | 0 |
| 13 | 7715707299 |
| 14 | 545539395584 |
| 15 | 42297694603648 |
| 16 | 4883188189089105 |
| 17 | 531361846217471443 |
| 18 | 0 |
| 19 | 28649272821614715410221 |
| 20 | 14214363393075742724609375 |
| 21 | 7526219790642312236217153392 |
| 22 | 5968603205606800870499639536231 |
[1,1,2,5,11,0,232,2295,26714,453871,7053157,0, 7715707299,545539395584,42297694603648, 4883188189089105,531361846217471443,0, 28649272821614715410221, 14214363393075742724609375, 7526219790642312236217153392, 5968603205606800870499639536231] |