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 | 7 |
| 2 | 49 |
| 3 | 230 |
| 4 | 1209 |
| 5 | 6475 |
| 6 | 34020 |
| 7 | 179097 |
| 8 | 944514 |
| 9 | 4978956 |
| 10 | 26241679 |
| 11 | 138316703 |
| 12 | 729070278 |
| 13 | 3842881010 |
| 14 | 20255521442 |
| 15 | 106765644778 |
| 16 | 562755120940 |
| 17 | 2966245831625 |
| 18 | 15634892911279 |
| 19 | 82410528967137 |
| 20 | 434380653636920 |