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 | 4 |
| 2 | 20 |
| 3 | 77 |
| 4 | 326 |
| 5 | 1373 |
| 6 | 5793 |
| 7 | 24347 |
| 8 | 102398 |
| 9 | 431050 |
| 10 | 1813753 |
| 11 | 7631302 |
| 12 | 32111207 |
| 13 | 135119039 |
| 14 | 568549155 |
| 15 | 2392325744 |
| 16 | 10066404116 |
| 17 | 42357266765 |
| 18 | 178230161368 |
| 19 | 749953993371 |
| 20 | 3155644584471 |
| 21 | 13278270334423 |
| 22 | 55872091215736 |