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| n | a(n) |
|---|---|
| 1 | 140 |
| 2 | 26816 |
| 3 | 852940 |
| 4 | 10077438 |
| 5 | 67449574 |
| 6 | 326423068 |
| 7 | 1218634086 |
| 8 | 3870426602 |
| 9 | 10678039872 |
| 10 | 26541186546 |
| 11 | 60515390904 |
| 12 | 129217908546 |
| 13 | 258501393812 |
| 14 | 493822993858 |
| 15 | 903540678414 |
| 16 | 1589111278140 |
| 17 | 2702453254684 |
| 18 | 4467233004764 |
[140,26816,852940,10077438,67449574,326423068, 1218634086,3870426602,10678039872,26541186546, 60515390904,129217908546,258501393812, 493822993858,903540678414,1589111278140, 2702453254684,4467233004764] |