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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 10 |
| 4 | 105 |
| 5 | 1326 |
| 6 | 20503 |
| 7 | 384126 |
| 8 | 8567730 |
| 9 | 223587231 |
| 10 | 6725042325 |
| 11 | 230228283165 |
| 12 | 8877197732406 |
| 13 | 382107434701266 |
| 14 | 18221275474580181 |
| 15 | 956287167902779240 |
| 16 | 54916689705422813731 |
| 17 | 3433293323775503064306 |
| 18 | 232614384749689991763561 |
| 19 | 17010440815323680947084096 |
[0,0,1,10,105,1326,20503,384126,8567730,223587231, 6725042325,230228283165,8877197732406, 382107434701266,18221275474580181, 956287167902779240,54916689705422813731, 3433293323775503064306,232614384749689991763561, 17010440815323680947084096] |