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 | 2 |
| 3 | 12 |
| 4 | 152 |
| 5 | 3640 |
| 6 | 160224 |
| 7 | 13063792 |
| 8 | 2012388736 |
| 9 | 596666619648 |
| 10 | 344964885948160 |
| 11 | 392058233038486784 |
| 12 | 880255154481199466496 |
| 13 | 3916538634445633156373504 |
| 14 | 34603083354426212294072477696 |
| 15 | 607915214065957203519146330173440 |