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 | 1 |
| 4 | 3 |
| 5 | 5 |
| 6 | 13 |
| 7 | 35 |
| 8 | 95 |
| 9 | 255 |
| 10 | 715 |
| 11 | 2081 |
| 12 | 6003 |
| 13 | 17645 |
| 14 | 52127 |
| 15 | 155863 |
| 16 | 468129 |
| 17 | 1415521 |
| 18 | 4301055 |
| 19 | 13134789 |
| 20 | 40275109 |
| 21 | 123970669 |
| 22 | 382919917 |
| 23 | 1186475687 |
| 24 | 3686899725 |
| 25 | 11487023793 |
| 26 | 35876838669 |
| 27 | 112304155021 |
| 28 | 352276801491 |