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) |
|---|---|
| 3 | 1 |
| 4 | 12 |
| 5 | 95 |
| 6 | 629 |
| 7 | 3781 |
| 8 | 21433 |
| 9 | 116928 |
| 10 | 621317 |
| 11 | 3239925 |
| 12 | 16662600 |
| 13 | 84804868 |
| 14 | 428176176 |
| 15 | 2148404051 |
| 16 | 10726889402 |
| 17 | 53349600116 |
| 18 | 264499086453 |
| 19 | 1308025259637 |
| 20 | 6455291067020 |
| 21 | 31804649415803 |
| 22 | 156486128169860 |
| 23 | 769098411417361 |