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 | 1 |
| 2 | 55 |
| 3 | 595 |
| 4 | 9028 |
| 5 | 127707 |
| 6 | 1830234 |
| 7 | 26160354 |
| 8 | 374285478 |
| 9 | 5353011036 |
| 10 | 76569060586 |
| 11 | 1095191883209 |
| 12 | 15665062073662 |
| 13 | 224064344818735 |
| 14 | 3204894379079451 |
| 15 | 45841053844805851 |
| 16 | 655685372871482854 |
| 17 | 9378564896063570084 |
| 18 | 134145862914757375163 |
| 19 | 1918749051397966520006 |