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 | 13 |
| 3 | 127 |
| 4 | 1105 |
| 5 | 1255 |
| 6 | 24337 |
| 7 | 263671 |
| 8 | 725953 |
| 9 | 42823 |
| 10 | 40610545 |
| 11 | 163341463 |
| 12 | 780593185 |
| 13 | 5464152295 |
| 14 | 51309760081 |
| 15 | 45711664183 |
| 16 | 2200721587585 |
| 17 | 12583941205639 |
| 18 | 3454291215793 |
| 19 | 430419865184215 |
| 20 | 3012939056289505 |
| 21 | 10122098073837607 |
| 22 | 92791637157241105 |
| 23 | 517919756258420599 |