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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 343 |
| 3 | 17576 |
| 4 | 250047 |
| 5 | 1906624 |
| 6 | 9938375 |
| 7 | 40001688 |
| 8 | 133432831 |
| 9 | 385828352 |
| 10 | 997002999 |
| 11 | 2352637000 |
| 12 | 5150827583 |
| 13 | 10590025536 |
| 14 | 20638466407 |
| 15 | 38409197624 |
| 16 | 68669157375 |
| 17 | 118515478528 |
| 18 | 198257271191 |
| 19 | 322546580712 |
| 20 | 511808023999 |
[0,343,17576,250047,1906624,9938375,40001688, 133432831,385828352,997002999,2352637000, 5150827583,10590025536,20638466407,38409197624, 68669157375,118515478528,198257271191, 322546580712,511808023999] |