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| n | a(n) |
|---|---|
| 0 | 20 |
| 1 | 420 |
| 2 | 1620 |
| 3 | 3620 |
| 4 | 6420 |
| 5 | 10020 |
| 6 | 14420 |
| 7 | 19620 |
| 8 | 25620 |
| 9 | 32420 |
| 10 | 40020 |
| 11 | 48420 |
| 12 | 57620 |
| 13 | 67620 |
| 14 | 78420 |
| 15 | 90020 |
| 16 | 102420 |
| 17 | 115620 |
| 18 | 129620 |
| 19 | 144420 |
| 20 | 160020 |
| 21 | 176420 |
| 22 | 193620 |
| 23 | 211620 |
| 24 | 230420 |
| 25 | 250020 |
| 26 | 270420 |
| 27 | 291620 |
| 28 | 313620 |
| 29 | 336420 |
| 30 | 360020 |
| 31 | 384420 |
| 32 | 409620 |
| 33 | 435620 |
| 34 | 462420 |
| 35 | 490020 |
[20,420,1620,3620,6420,10020,14420,19620,25620, 32420,40020,48420,57620,67620,78420,90020,102420, 115620,129620,144420,160020,176420,193620,211620, 230420,250020,270420,291620,313620,336420,360020, 384420,409620,435620,462420,490020] |