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 | 2 |
| 2 | 11 |
| 3 | 62 |
| 4 | 367 |
| 5 | 2232 |
| 6 | 13820 |
| 7 | 86662 |
| 8 | 548591 |
| 9 | 3498146 |
| 10 | 22436251 |
| 11 | 144583496 |
| 12 | 935394436 |
| 13 | 6071718512 |
| 14 | 39523955552 |
| 15 | 257913792342 |
| 16 | 1686627623151 |
| 17 | 11050540084902 |
| 18 | 72522925038257 |
| 19 | 476669316338542 |
| 20 | 3137209052543927 |
| 21 | 20672732229560032 |
| 22 | 136374124374593072 |
| 23 | 900541325129687272 |