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 | 2 |
| 2 | 2 |
| 3 | 5 |
| 4 | 13 |
| 5 | 40 |
| 6 | 128 |
| 7 | 457 |
| 8 | 1660 |
| 9 | 6308 |
| 10 | 24409 |
| 11 | 96363 |
| 12 | 385535 |
| 13 | 1561706 |
| 14 | 6387135 |
| 15 | 26347199 |
| 16 | 109471366 |
| 17 | 457758461 |
| 18 | 1924845582 |
| 19 | 8134171456 |
| 20 | 34526723986 |
| 21 | 147139513066 |
| 22 | 629314845284 |
| 23 | 2700401538933 |
| 24 | 11622130671430 |