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 | 6 |
| 3 | 117 |
| 4 | 4388 |
| 5 | 266065 |
| 6 | 23731314 |
| 7 | 2923345621 |
| 8 | 475364541672 |
| 9 | 98623225721601 |
| 10 | 25421365316232710 |
| 11 | 7969388199705535141 |
| 12 | 2985785305877403047820 |
| 13 | 1317500933136749853197329 |
| 14 | 676266417871227455138941242 |
| 15 | 399516621958550611386236160405 |