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) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 15 |
| 4 | 87 |
| 5 | 201 |
| 6 | 3123 |
| 7 | 5769 |
| 8 | 148347 |
| 9 | 913761 |
| 10 | 11541123 |
| 11 | 39975849 |
| 12 | 2616723387 |
| 13 | 6227552241 |
| 14 | 230557039443 |
| 15 | 4151870901369 |
| 16 | 76980002233707 |
| 17 | 355687471142721 |
| 18 | 27886053280896963 |
| 19 | 121645100796252489 |
| 20 | 10474674957482235867 |
| 21 | 135117295282596928401 |
| 22 | 2811664555920692775603 |