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 | 4 |
| 3 | 19 |
| 4 | 98 |
| 5 | 531 |
| 6 | 2974 |
| 7 | 17060 |
| 8 | 99658 |
| 9 | 590563 |
| 10 | 3540464 |
| 11 | 21430267 |
| 12 | 130771376 |
| 13 | 803538100 |
| 14 | 4967127736 |
| 15 | 30866224824 |
| 16 | 192696614730 |
| 17 | 1207967820099 |
| 18 | 7600482116932 |
| 19 | 47981452358201 |
| 20 | 303820299643138 |
| 21 | 1929099000980219 |
| 22 | 12279621792772822 |
| 23 | 78346444891033856 |