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 | 7 |
| 4 | 29 |
| 5 | 136 |
| 6 | 737 |
| 7 | 4537 |
| 8 | 30914 |
| 9 | 229831 |
| 10 | 1850717 |
| 11 | 16036912 |
| 12 | 148573889 |
| 13 | 1463520241 |
| 14 | 15259826402 |
| 15 | 167789512807 |
| 16 | 1939125333629 |
| 17 | 23484982837816 |
| 18 | 297289975208417 |
| 19 | 3924325664733097 |
| 20 | 53906145745657634 |
| 21 | 769095929901073831 |
| 22 | 11377500925452103037 |
| 23 | 174244037885068510432 |