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 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 15 |
| 5 | 52 |
| 6 | 203 |
| 7 | 876 |
| 8 | 4131 |
| 9 | 21065 |
| 10 | 115274 |
| 11 | 672673 |
| 12 | 4163743 |
| 13 | 27216840 |
| 14 | 187160429 |
| 15 | 1349511178 |
| 16 | 10173555345 |
| 17 | 79982663997 |
| 18 | 654277037674 |
| 19 | 5557624876513 |
| 20 | 48931106059451 |
| 21 | 445790174654588 |
| 22 | 4196351007814659 |
| 23 | 40757862664061104 |
| 24 | 407944375184911787 |