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) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 34 |
| 4 | 147 |
| 5 | 684 |
| 6 | 3341 |
| 7 | 16896 |
| 8 | 87702 |
| 9 | 464566 |
| 10 | 2501178 |
| 11 | 13646625 |
| 12 | 75289022 |
| 13 | 419301351 |
| 14 | 2354121750 |
| 15 | 13309905653 |
| 16 | 75715795119 |
| 17 | 433063793430 |
| 18 | 2488921730886 |
| 19 | 14366319150072 |
| 20 | 83246947358766 |
| 21 | 484082947060300 |
| 22 | 2823980738817453 |
| 23 | 16522429720210884 |
| 24 | 96928401308507100 |