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| n | a(n) |
|---|---|
| 1 | 18 |
| 2 | 340 |
| 3 | 2022 |
| 4 | 7400 |
| 5 | 20602 |
| 6 | 48060 |
| 7 | 99022 |
| 8 | 186064 |
| 9 | 325602 |
| 10 | 538404 |
| 11 | 850102 |
| 12 | 1291704 |
| 13 | 1900106 |
| 14 | 2718604 |
| 15 | 3797406 |
| 16 | 5194144 |
| 17 | 6974386 |
| 18 | 9212148 |
| 19 | 11990406 |
| 20 | 15401608 |
| 21 | 19548186 |
| 22 | 24543068 |
| 23 | 30510190 |
| 24 | 37585008 |
| 25 | 45915010 |
| 26 | 55660228 |
| 27 | 66993750 |
| 28 | 80102232 |
| 29 | 95186410 |
| 30 | 112461612 |
[18,340,2022,7400,20602,48060,99022,186064,325602, 538404,850102,1291704,1900106,2718604,3797406, 5194144,6974386,9212148,11990406,15401608, 19548186,24543068,30510190,37585008,45915010, 55660228,66993750,80102232,95186410,112461612] |