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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 5 |
| 3 | 6 |
| 4 | 7 |
| 5 | 9 |
| 6 | 12 |
| 7 | 73 |
| 8 | 129 |
| 9 | 142 |
| 10 | 144 |
| 11 | 253 |
| 12 | 455 |
| 13 | 531 |
| 14 | 734 |
| 15 | 1009 |
| 16 | 1193 |
| 17 | 1553 |
| 18 | 2449 |
| 19 | 3309 |
| 20 | 13534 |
| 21 | 17513 |
| 22 | 17832 |
| 23 | 22852 |
[4,5,6,7,9,12,73,129,142,144,253,455,531,734,1009, 1193,1553,2449,3309,13534,17513,17832,22852] |