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 | 5 |
| 2 | 9 |
| 3 | 25 |
| 4 | 71 |
| 5 | 311 |
| 6 | 479 |
| 7 | 1559 |
| 8 | 5711 |
| 9 | 10559 |
| 10 | 18191 |
| 11 | 31391 |
| 12 | 118271 |
| 13 | 701399 |
| 14 | 366791 |
| 15 | 2704679 |
| 16 | 2954591 |
| 17 | 2155919 |
| 18 | 13845841 |
| 19 | 6077111 |
| 20 | 25411681 |
| 21 | 28398241 |