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 | 3 |
| 3 | 13 |
| 4 | 76 |
| 5 | 521 |
| 6 | 3996 |
| 7 | 32923 |
| 8 | 286202 |
| 9 | 2590347 |
| 10 | 24203935 |
| 11 | 232050202 |
| 12 | 2272449745 |
| 13 | 22653570386 |
| 14 | 229274897514 |
| 15 | 2350933487206 |
| 16 | 24381053759852 |
| 17 | 255382755251622 |
| 18 | 2698732882975782 |
| 19 | 28743579211912338 |