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 | 5 |
| 2 | 189 |
| 3 | 3633 |
| 4 | 83374 |
| 5 | 1817897 |
| 6 | 40220893 |
| 7 | 886130549 |
| 8 | 19546906987 |
| 9 | 431024540644 |
| 10 | 9505433227293 |
| 11 | 209617856008535 |
| 12 | 4622624792880217 |
| 13 | 101940750143038657 |
| 14 | 2248057208102711472 |
| 15 | 49575464007447758483 |
| 16 | 1093267021618939507743 |
| 17 | 24109360928450426884813 |
| 18 | 531673668551361276666101 |