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 | 10 |
| 3 | 18 |
| 4 | 63 |
| 5 | 132 |
| 6 | 3692 |
| 7 | 8025 |
| 8 | 9200 |
| 9 | 13205 |
| 10 | 16275 |
| 11 | 287382 |
| 12 | 1674342 |
| 13 | 13852716 |
| 14 | 261109560 |
| 15 | 509099424 |
| 16 | 53226407187 |
| 17 | 339194408709 |
| 18 | 63673280091408 |
| 19 | 230160748303410 |
| 20 | 9613333448250222 |
| 21 | 14247374595414090 |
| 22 | 446710602178803172 |