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 | 7 |
| 4 | 13 |
| 5 | 28 |
| 6 | 72 |
| 7 | 217 |
| 8 | 741 |
| 9 | 2790 |
| 10 | 11388 |
| 11 | 49875 |
| 12 | 232781 |
| 13 | 1151928 |
| 14 | 6018800 |
| 15 | 33087221 |
| 16 | 190780229 |
| 17 | 1150653938 |
| 18 | 7241710948 |
| 19 | 47454745823 |
| 20 | 323154696205 |
| 21 | 2282779990516 |
| 22 | 16700904488728 |
| 23 | 126356632390321 |
| 24 | 987303454928997 |