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 | 18 |
| 2 | 306 |
| 3 | 5202 |
| 4 | 88434 |
| 5 | 1503378 |
| 6 | 25557426 |
| 7 | 434476242 |
| 8 | 7386096114 |
| 9 | 125563633938 |
| 10 | 2134581776946 |
| 11 | 36287890208082 |
| 12 | 616894133537394 |
| 13 | 10487200270135698 |
| 14 | 178282404592306866 |
| 15 | 3030800878069216722 |
| 16 | 51523614927176684274 |
| 17 | 875901453762003632658 |
| 18 | 14890324713954061755186 |