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| n | a(n) |
|---|---|
| 1 | 111 |
| 2 | 221 |
| 3 | 222 |
| 4 | 322 |
| 5 | 331 |
| 6 | 332 |
| 7 | 333 |
| 8 | 432 |
| 9 | 433 |
| 10 | 441 |
| 11 | 442 |
| 12 | 443 |
| 13 | 444 |
| 14 | 533 |
| 15 | 542 |
| 16 | 543 |
| 17 | 544 |
| 18 | 551 |
| 19 | 552 |
| 20 | 553 |
| 21 | 554 |
| 22 | 555 |
| 23 | 643 |
| 24 | 644 |
| 25 | 652 |
| 26 | 653 |
| 27 | 654 |
| 28 | 655 |
| 29 | 661 |
| 30 | 662 |
| 31 | 663 |
| 32 | 664 |
| 33 | 665 |
| 34 | 666 |
| 35 | 744 |
| 36 | 753 |
| 37 | 754 |
| 38 | 755 |
| 39 | 762 |
| 40 | 763 |
| 41 | 764 |
| 42 | 765 |
| 43 | 766 |
| 44 | 771 |
| 45 | 772 |
| 46 | 773 |
| 47 | 774 |
| 48 | 775 |
| 49 | 776 |
| 50 | 777 |
| 51 | 854 |
| 52 | 855 |
[111,221,222,322,331,332,333,432,433,441,442,443, 444,533,542,543,544,551,552,553,554,555,643,644, 652,653,654,655,661,662,663,664,665,666,744,753, 754,755,762,763,764,765,766,771,772,773,774,775, 776,777,854,855] |