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 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 26 |
| 6 | 70 |
| 7 | 192 |
| 8 | 534 |
| 9 | 1500 |
| 10 | 4246 |
| 11 | 12092 |
| 12 | 34606 |
| 13 | 99442 |
| 14 | 286730 |
| 15 | 829168 |
| 16 | 2403834 |
| 17 | 6984234 |
| 18 | 20331558 |
| 19 | 59287740 |
| 20 | 173149662 |
| 21 | 506376222 |
| 22 | 1482730098 |
| 23 | 4346486256 |
| 24 | 12754363650 |
| 25 | 37461564504 |
| 26 | 110125172682 |
| 27 | 323990062452 |
| 28 | 953883382354 |