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 | 24 |
| 2 | 196 |
| 3 | 1644 |
| 4 | 13916 |
| 5 | 118416 |
| 6 | 1010892 |
| 7 | 8648028 |
| 8 | 74086762 |
| 9 | 635291688 |
| 10 | 5451042614 |
| 11 | 46791744232 |
| 12 | 401773647392 |
| 13 | 3450448765596 |
| 14 | 29636332554924 |
| 15 | 254571572184234 |
| 16 | 2186853928177032 |
| 17 | 18786503501683672 |
| 18 | 161392382824498244 |