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 | 6 |
| 4 | 23 |
| 5 | 101 |
| 6 | 484 |
| 7 | 2468 |
| 8 | 13166 |
| 9 | 72630 |
| 10 | 411076 |
| 11 | 2374188 |
| 12 | 13938018 |
| 13 | 82932254 |
| 14 | 499031324 |
| 15 | 3031610924 |
| 16 | 18568429963 |
| 17 | 114541486785 |
| 18 | 710973143614 |
| 19 | 4437415155234 |
| 20 | 27831038618735 |
| 21 | 175318861863701 |
| 22 | 1108762012137252 |
| 23 | 7037137177329268 |
| 24 | 44808588430903068 |