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) |
|---|---|
| 3 | 2 |
| 4 | 7 |
| 5 | 36 |
| 6 | 182 |
| 7 | 1056 |
| 8 | 6669 |
| 9 | 46348 |
| 10 | 350240 |
| 11 | 2866632 |
| 12 | 25260211 |
| 13 | 238550196 |
| 14 | 2403846954 |
| 15 | 25749417440 |
| 16 | 292191829273 |
| 17 | 3501634042140 |
| 18 | 44194287012404 |
| 19 | 585947863072440 |
| 20 | 8142408896706495 |
| 21 | 118341851934179140 |
| 22 | 1795485894869716670 |
| 23 | 28386889319060192592 |