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 | 4 |
| 1 | 33 |
| 2 | 268 |
| 3 | 2177 |
| 4 | 17684 |
| 5 | 143649 |
| 6 | 1166876 |
| 7 | 9478657 |
| 8 | 76996132 |
| 9 | 625447713 |
| 10 | 5080577836 |
| 11 | 41270070401 |
| 12 | 335241141044 |
| 13 | 2723199198753 |
| 14 | 22120834731068 |
| 15 | 179689877047297 |
| 16 | 1459639851109444 |
| 17 | 11856808685922849 |
| 18 | 96314109338492236 |