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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 5 |
| 7 | 27 |
| 8 | 167 |
| 9 | 5204 |
| 10 | 177103 |
| 11 | 14527650 |
| 12 | 959002003 |
| 13 | 94955725947 |
| 14 | 4084055217724 |
| 15 | 179793385305803 |
| 16 | 120106065439494128 |
| 17 | 183522247784932333387 |
| 18 | 256013655766046044568993 |
| 19 | 173321428475860957105541648 |
[0,1,0,1,1,2,5,27,167,5204,177103,14527650, 959002003,94955725947,4084055217724, 179793385305803,120106065439494128, 183522247784932333387,256013655766046044568993, 173321428475860957105541648] |