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 | 0 |
| 2 | 12 |
| 3 | 149 |
| 4 | 1712 |
| 5 | 18744 |
| 6 | 198062 |
| 7 | 2050696 |
| 8 | 20959322 |
| 9 | 212385942 |
| 10 | 2139236881 |
| 11 | 21454599814 |
| 12 | 214499908019 |
| 13 | 2139634739326 |
| 14 | 21306682904040 |
| 15 | 211905511283590 |
| 16 | 2105504493045818 |
| 17 | 20905484578206982 |
| 18 | 207458897819329031 |
| 19 | 2057931819347474462 |