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 | 15 |
| 3 | 63 |
| 4 | 135 |
| 5 | 567 |
| 6 | 315 |
| 7 | 5103 |
| 8 | 1155 |
| 9 | 1575 |
| 10 | 2835 |
| 11 | 413343 |
| 12 | 4095 |
| 13 | 3720087 |
| 14 | 25515 |
| 15 | 14175 |
| 16 | 10395 |
| 17 | 301327047 |
| 18 | 20475 |
| 19 | 2711943423 |
| 20 | 36855 |
| 21 | 127575 |
| 22 | 2066715 |
| 23 | 219667417263 |
| 24 | 51975 |
| 25 | 354375 |
| 26 | 18600435 |
| 27 | 121275 |
| 28 | 331695 |
| 29 | 160137547184727 |
| 30 | 184275 |
| 31 | 1441237924662543 |
| 32 | 135135 |