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 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 22 |
| 4 | 91 |
| 5 | 413 |
| 6 | 2032 |
| 7 | 10754 |
| 8 | 60832 |
| 9 | 365815 |
| 10 | 2327835 |
| 11 | 15612872 |
| 12 | 109992442 |
| 13 | 811500784 |
| 14 | 6253327841 |
| 15 | 50211976959 |
| 16 | 419239644142 |
| 17 | 3632891419054 |
| 18 | 32616077413970 |
| 19 | 302915722319509 |
| 20 | 2906047810600157 |
| 21 | 28761123170398258 |
| 22 | 293296874302640254 |
| 23 | 3078390856651377534 |
| 24 | 33220524976632438215 |