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 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 17 |
| 6 | 129 |
| 7 | 823 |
| 8 | 16549 |
| 9 | 203762 |
| 10 | 9057969 |
| 11 | 229117047 |
| 12 | 20251050469 |
| 13 | 1099941609906 |
| 14 | 182745344595201 |
| 15 | 21826976698036317 |
| 16 | 6625997170286326085 |
| 17 | 1760792727174811634066 |
| 18 | 963263479575497024110193 |
| 19 | 572732462137043288595101258 |
| 20 | 560867188756075075604736149189 |