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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 63 |
| 3 | 77 |
| 4 | 147 |
| 5 | 189 |
| 6 | 221 |
| 7 | 437 |
| 8 | 441 |
| 9 | 539 |
| 10 | 567 |
| 11 | 847 |
| 12 | 1029 |
| 13 | 1323 |
| 14 | 1517 |
| 15 | 1701 |
| 16 | 2021 |
| 17 | 2873 |
| 18 | 3087 |
| 19 | 3757 |
| 20 | 3773 |
| 21 | 3969 |
| 22 | 4757 |
| 23 | 5103 |
| 24 | 5929 |
| 25 | 6557 |
| 26 | 7203 |
| 27 | 8303 |
| 28 | 9261 |
| 29 | 9317 |
| 30 | 9797 |
| 31 | 10051 |
| 32 | 11021 |
| 33 | 11907 |
| 34 | 12317 |
| 35 | 15309 |
| 36 | 16637 |
| 37 | 21609 |
[21,63,77,147,189,221,437,441,539,567,847,1029, 1323,1517,1701,2021,2873,3087,3757,3773,3969,4757, 5103,5929,6557,7203,8303,9261,9317,9797,10051, 11021,11907,12317,15309,16637,21609] |