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 | 2 |
| 2 | 7 |
| 3 | 29 |
| 4 | 127 |
| 5 | 572 |
| 6 | 2623 |
| 7 | 12182 |
| 8 | 57115 |
| 9 | 269750 |
| 10 | 1281457 |
| 11 | 6116585 |
| 12 | 29310721 |
| 13 | 140925176 |
| 14 | 679493983 |
| 15 | 3284357789 |
| 16 | 15909178627 |
| 17 | 77208716606 |
| 18 | 375330428293 |
| 19 | 1827310839359 |
| 20 | 8908332730957 |
| 21 | 43481990059796 |
| 22 | 212472526927393 |