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 | 3 |
| 3 | 11 |
| 4 | 42 |
| 5 | 168 |
| 6 | 696 |
| 7 | 2965 |
| 8 | 12915 |
| 9 | 57276 |
| 10 | 257787 |
| 11 | 1174597 |
| 12 | 5407854 |
| 13 | 25119663 |
| 14 | 117579351 |
| 15 | 554053049 |
| 16 | 2626184688 |
| 17 | 12513029640 |
| 18 | 59898952650 |
| 19 | 287931365692 |
| 20 | 1389297316104 |
| 21 | 6726449251539 |
| 22 | 32668497856323 |
| 23 | 159114598216251 |