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| n | a(n) |
|---|---|
| 4 | 0 |
| 5 | 1 |
| 6 | 2 |
| 7 | 31 |
| 8 | 264 |
| 9 | 2783 |
| 10 | 30818 |
| 11 | 369321 |
| 12 | 4745952 |
| 13 | 65275999 |
| 14 | 957874226 |
| 15 | 14951584189 |
| 16 | 247524019720 |
| 17 | 4334022049377 |
| 18 | 80052395326514 |
| 19 | 1555999253409203 |
| 20 | 31755107852542144 |
| 21 | 679008663143893773 |
| 22 | 15182701602959054546 |
| 23 | 354364531995856105099 |
| 24 | 8618865446674052425224 |
[0,1,2,31,264,2783,30818,369321,4745952,65275999, 957874226,14951584189,247524019720,4334022049377, 80052395326514,1555999253409203,31755107852542144, 679008663143893773,15182701602959054546, 354364531995856105099,8618865446674052425224] |