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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 33 |
| 3 | 63 |
| 4 | 69 |
| 5 | 81 |
| 6 | 99 |
| 7 | 111 |
| 8 | 123 |
| 9 | 159 |
| 10 | 165 |
| 11 | 183 |
| 12 | 189 |
| 13 | 203 |
| 14 | 207 |
| 15 | 219 |
| 16 | 231 |
| 17 | 237 |
| 18 | 243 |
| 19 | 249 |
| 20 | 259 |
| 21 | 261 |
| 22 | 273 |
| 23 | 297 |
| 24 | 303 |
| 25 | 315 |
| 26 | 321 |
| 27 | 363 |
| 28 | 399 |
| 29 | 411 |
| 30 | 423 |
| 31 | 429 |
| 32 | 435 |
| 33 | 441 |
| 34 | 459 |
| 35 | 483 |
| 36 | 489 |
| 37 | 495 |
| 38 | 513 |
| 39 | 543 |
| 40 | 561 |
| 41 | 567 |
| 42 | 573 |
| 43 | 585 |
| 44 | 591 |
| 45 | 603 |
| 46 | 615 |
| 47 | 621 |
| 48 | 627 |
| 49 | 633 |
| 50 | 663 |
| 51 | 669 |
| 52 | 693 |
| 53 | 707 |
| 54 | 711 |
[21,33,63,69,81,99,111,123,159,165,183,189,203, 207,219,231,237,243,249,259,261,273,297,303,315, 321,363,399,411,423,429,435,441,459,483,489,495, 513,543,561,567,573,585,591,603,615,621,627,633, 663,669,693,707,711] |