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 | 1 |
| 3 | 4 |
| 4 | 13 |
| 5 | 51 |
| 6 | 197 |
| 7 | 875 |
| 8 | 4096 |
| 9 | 20643 |
| 10 | 109246 |
| 11 | 601491 |
| 12 | 3402911 |
| 13 | 19628063 |
| 14 | 114699438 |
| 15 | 676207572 |
| 16 | 4010086352 |
| 17 | 23874362199 |
| 18 | 142508702805 |
| 19 | 852124263683 |
| 20 | 5101098123207 |
| 21 | 30560194492576 |
| 22 | 183176169456214 |