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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 41 |
| 5 | 512 |
| 6 | 8285 |
| 7 | 166582 |
| 8 | 4054953 |
| 9 | 116797432 |
| 10 | 3912076929 |
| 11 | 150190759240 |
| 12 | 6532014077809 |
| 13 | 318632936830136 |
| 14 | 17286883399233149 |
| 15 | 1035508343364348938 |
| 16 | 68053563847088272945 |
| 17 | 4879593083836366195728 |
| 18 | 379847137967853770523937 |
| 19 | 31960371880691511556886988 |
[1,0,1,4,41,512,8285,166582,4054953,116797432, 3912076929,150190759240,6532014077809, 318632936830136,17286883399233149, 1035508343364348938,68053563847088272945, 4879593083836366195728,379847137967853770523937, 31960371880691511556886988] |