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 | 14 |
| 3 | 149 |
| 4 | 1428 |
| 5 | 12989 |
| 6 | 114730 |
| 7 | 995737 |
| 8 | 8548008 |
| 9 | 72872473 |
| 10 | 618458246 |
| 11 | 5233409213 |
| 12 | 44200191420 |
| 13 | 372832446869 |
| 14 | 3142245259426 |
| 15 | 26468308629121 |
| 16 | 222870793614672 |
| 17 | 1876180605036721 |
| 18 | 15791601170624510 |
| 19 | 132901927952017253 |