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 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 8 |
| 5 | 24 |
| 6 | 75 |
| 7 | 243 |
| 8 | 808 |
| 9 | 2742 |
| 10 | 9458 |
| 11 | 33062 |
| 12 | 116868 |
| 13 | 417022 |
| 14 | 1500159 |
| 15 | 5434563 |
| 16 | 19808976 |
| 17 | 72596742 |
| 18 | 267343374 |
| 19 | 988779258 |
| 20 | 3671302176 |
| 21 | 13679542632 |
| 22 | 51134644014 |
| 23 | 191703766638 |
| 24 | 720629997168 |
| 25 | 2715610275804 |
| 26 | 10256844598900 |
| 27 | 38822029694628 |
| 28 | 147229736485868 |