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 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 30 |
| 6 | 98 |
| 7 | 328 |
| 8 | 1140 |
| 9 | 4040 |
| 10 | 14542 |
| 11 | 53060 |
| 12 | 195624 |
| 13 | 727790 |
| 14 | 2728450 |
| 15 | 10296720 |
| 16 | 39084190 |
| 17 | 149115456 |
| 18 | 571504686 |
| 19 | 2199310460 |
| 20 | 8494701152 |
| 21 | 32919635606 |
| 22 | 127961125094 |
| 23 | 498775164568 |
| 24 | 1949112527750 |
| 25 | 7634623480172 |