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 | 4 |
| 3 | 9 |
| 4 | 19 |
| 5 | 42 |
| 6 | 90 |
| 7 | 197 |
| 8 | 424 |
| 9 | 923 |
| 10 | 1989 |
| 11 | 4315 |
| 12 | 9300 |
| 13 | 20129 |
| 14 | 43374 |
| 15 | 93724 |
| 16 | 201888 |
| 17 | 435713 |
| 18 | 938218 |
| 19 | 2022972 |
| 20 | 4354569 |
| 21 | 9382489 |
| 22 | 20190181 |
| 23 | 43477688 |
| 24 | 93534469 |
| 25 | 201326672 |
| 26 | 433017364 |
| 27 | 931701321 |
| 28 | 2003520121 |
| 29 | 4309597827 |
| 30 | 9265723250 |