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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 20 |
| 5 | 24 |
| 6 | 54 |
| 7 | 60 |
| 8 | 61 |
| 9 | 62 |
| 10 | 72 |
| 11 | 73 |
| 12 | 74 |
| 13 | 504 |
| 14 | 510 |
| 15 | 511 |
| 16 | 512 |
| 17 | 560 |
| 18 | 564 |
| 19 | 1512 |
| 20 | 1513 |
| 21 | 1514 |
| 22 | 1520 |
| 23 | 1620 |
| 24 | 1621 |
| 25 | 1622 |
| 26 | 6320 |
| 27 | 6324 |
| 28 | 6372 |
| 29 | 6373 |
| 30 | 6374 |
| 31 | 6500 |
| 32 | 6504 |
| 33 | 6552 |
| 34 | 6553 |
| 35 | 6554 |
| 36 | 6560 |
| 37 | 13122 |
| 38 | 13123 |
| 39 | 13124 |
| 40 | 13770 |
| 41 | 13771 |
| 42 | 13772 |
| 43 | 13824 |
| 44 | 13850 |
| 45 | 15072 |
| 46 | 15073 |
| 47 | 15074 |
[0,1,2,20,24,54,60,61,62,72,73,74,504,510,511,512, 560,564,1512,1513,1514,1520,1620,1621,1622,6320, 6324,6372,6373,6374,6500,6504,6552,6553,6554,6560, 13122,13123,13124,13770,13771,13772,13824,13850, 15072,15073,15074] |