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 | 3 |
| 4 | 9 |
| 5 | 34 |
| 6 | 135 |
| 7 | 610 |
| 8 | 2965 |
| 9 | 15612 |
| 10 | 87871 |
| 11 | 526274 |
| 12 | 3334850 |
| 13 | 22270254 |
| 14 | 156172689 |
| 15 | 1146640394 |
| 16 | 8791424549 |
| 17 | 70227355786 |
| 18 | 583283741066 |
| 19 | 5027823752930 |
| 20 | 44903579626132 |
| 21 | 414877600876638 |
| 22 | 3959945232723603 |
| 23 | 38996757506464858 |
| 24 | 395749369598406027 |
| 25 | 4134132167178705732 |