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 | 5 |
| 2 | 50 |
| 3 | 256 |
| 4 | 1402 |
| 5 | 6940 |
| 6 | 33502 |
| 7 | 157279 |
| 8 | 725080 |
| 9 | 3293575 |
| 10 | 14789640 |
| 11 | 65785991 |
| 12 | 290341336 |
| 13 | 1272947979 |
| 14 | 5549535668 |
| 15 | 24075671345 |
| 16 | 104002776564 |
| 17 | 447586575256 |
| 18 | 1919810662952 |
| 19 | 8210002538205 |
| 20 | 35015688030978 |
| 21 | 148980204943747 |
| 22 | 632466650426456 |
| 23 | 2679623444793841 |