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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 201 |
| 3 | 267 |
| 4 | 321 |
| 5 | 369 |
| 6 | 459 |
| 7 | 537 |
| 8 | 651 |
| 9 | 669 |
| 10 | 699 |
| 11 | 723 |
| 12 | 753 |
| 13 | 1071 |
| 14 | 1113 |
| 15 | 1197 |
| 16 | 1203 |
| 17 | 1209 |
| 18 | 1323 |
| 19 | 1401 |
| 20 | 1503 |
| 21 | 1587 |
| 22 | 1647 |
| 23 | 1773 |
| 24 | 1791 |
| 25 | 1797 |
| 26 | 1917 |
| 27 | 1941 |
| 28 | 2007 |
| 29 | 2139 |
| 30 | 2223 |
| 31 | 2427 |
| 32 | 2493 |
| 33 | 2613 |
| 34 | 2733 |
| 35 | 2769 |
| 36 | 2787 |
| 37 | 2847 |
| 38 | 3147 |
| 39 | 3249 |
| 40 | 3267 |
| 41 | 3297 |
| 42 | 3399 |
| 43 | 3423 |
| 44 | 3441 |
| 45 | 3771 |
[21,201,267,321,369,459,537,651,669,699,723,753, 1071,1113,1197,1203,1209,1323,1401,1503,1587,1647, 1773,1791,1797,1917,1941,2007,2139,2223,2427,2493, 2613,2733,2769,2787,2847,3147,3249,3267,3297,3399, 3423,3441,3771] |