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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 20 |
| 3 | 80 |
| 4 | 320 |
| 5 | 1280 |
| 6 | 5120 |
| 7 | 20480 |
| 8 | 81920 |
| 9 | 327680 |
| 10 | 1310710 |
| 11 | 5242800 |
| 12 | 20971050 |
| 13 | 83883600 |
| 14 | 335532000 |
| 15 | 1342118400 |
| 16 | 5368435200 |
| 17 | 21473587200 |
| 18 | 85893734400 |
| 19 | 343572480000 |
| 20 | 1374280089690 |
| 21 | 5497081037820 |
| 22 | 21988166868630 |
| 23 | 87952038348420 |
[1,5,20,80,320,1280,5120,20480,81920,327680, 1310710,5242800,20971050,83883600,335532000, 1342118400,5368435200,21473587200,85893734400, 343572480000,1374280089690,5497081037820, 21988166868630,87952038348420] |