This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 21 |
| 3 | 63 |
| 4 | 189 |
| 5 | 567 |
| 6 | 693 |
| 7 | 3969 |
| 8 | 2079 |
| 9 | 5733 |
| 10 | 6237 |
| 11 | 413343 |
| 12 | 9009 |
| 13 | 74529 |
| 14 | 43659 |
| 15 | 51597 |
| 16 | 27027 |
| 17 | 1750329 |
| 18 | 63063 |
| 19 | 26040609 |
| 20 | 81081 |
| 21 | 464373 |
| 22 | 670761 |
| 23 | 219667417263 |
| 24 | 153153 |
| 25 | 2528253 |
| 26 | 819819 |
| 27 | 693693 |
| 28 | 729729 |
| 29 | 160137547184727 |
| 30 | 567567 |
| 31 | 6036849 |
| 32 | 459459 |
| 33 | 37614213 |
| 34 | 19253619 |