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 | 1 |
| 2 | 4 |
| 3 | 29 |
| 4 | 196 |
| 5 | 1781 |
| 6 | 14000 |
| 7 | 139234 |
| 8 | 1176340 |
| 9 | 12283166 |
| 10 | 108258380 |
| 11 | 1165438808 |
| 12 | 10561185568 |
| 13 | 116096795195 |
| 14 | 1072964739264 |
| 15 | 11975785105572 |
| 16 | 112313638368948 |
| 17 | 1268177365551626 |
| 18 | 12029082865935512 |
| 19 | 137067430786661911 |