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 | 13 |
| 3 | 44 |
| 4 | 140 |
| 5 | 446 |
| 6 | 1413 |
| 7 | 4471 |
| 8 | 14141 |
| 9 | 44720 |
| 10 | 141420 |
| 11 | 447213 |
| 12 | 1414213 |
| 13 | 4472135 |
| 14 | 14142135 |
| 15 | 44721359 |
| 16 | 141421355 |
| 17 | 447213594 |
| 18 | 1414213561 |
| 19 | 4472135954 |
| 20 | 14142135623 |
| 21 | 44721359549 |
| 22 | 141421356236 |
| 23 | 447213595499 |
| 24 | 1414213562372 |