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| n | a(n) |
|---|---|
| 1 | 18 |
| 2 | 72 |
| 3 | 1152 |
| 4 | 4050 |
| 5 | 15138 |
| 6 | 20808 |
| 7 | 46818 |
| 8 | 176418 |
| 9 | 206082 |
| 10 | 281250 |
| 11 | 362952 |
| 12 | 388962 |
| 13 | 472392 |
| 14 | 538722 |
| 15 | 734472 |
| 16 | 1080450 |
| 17 | 1152162 |
| 18 | 1566450 |
| 19 | 1685448 |
| 20 | 1808802 |
| 21 | 2268450 |
| 22 | 2544768 |
| 23 | 4339458 |
| 24 | 4464072 |
| 25 | 4536072 |
| 26 | 6118002 |
| 27 | 6329682 |
| 28 | 7746048 |
| 29 | 9305298 |
| 30 | 14612418 |
| 31 | 14709888 |
| 32 | 16623378 |
| 33 | 18471042 |
| 34 | 19244808 |
[18,72,1152,4050,15138,20808,46818,176418,206082, 281250,362952,388962,472392,538722,734472,1080450, 1152162,1566450,1685448,1808802,2268450,2544768, 4339458,4464072,4536072,6118002,6329682,7746048, 9305298,14612418,14709888,16623378,18471042, 19244808] |