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 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 10 |
| 5 | 31 |
| 6 | 271 |
| 7 | 1534 |
| 8 | 14393 |
| 9 | 117653 |
| 10 | 1253524 |
| 11 | 13140557 |
| 12 | 160679069 |
| 13 | 2026451948 |
| 14 | 28278471729 |
| 15 | 413532314433 |
| 16 | 6516434058758 |
| 17 | 107958571213579 |
| 18 | 1899723866781859 |
| 19 | 35092386753388698 |
| 20 | 682552407940860353 |
| 21 | 13893916425860413469 |
| 22 | 296049402365644855888 |