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 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 8 |
| 4 | 75 |
| 5 | 796 |
| 6 | 8051 |
| 7 | 73788 |
| 8 | 623155 |
| 9 | 4965836 |
| 10 | 38028051 |
| 11 | 283400668 |
| 12 | 2072874035 |
| 13 | 14966280876 |
| 14 | 107083717651 |
| 15 | 761327161148 |
| 16 | 5388524417715 |
| 17 | 38017832427916 |
| 18 | 267623218488851 |
| 19 | 1880883687651228 |
| 20 | 13203904989574195 |
| 21 | 92616374066478956 |
| 22 | 649261556308773651 |