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 | 4 |
| 3 | 8 |
| 4 | 19 |
| 5 | 51 |
| 6 | 141 |
| 7 | 392 |
| 8 | 1079 |
| 9 | 2957 |
| 10 | 8072 |
| 11 | 21987 |
| 12 | 59825 |
| 13 | 162695 |
| 14 | 442342 |
| 15 | 1202521 |
| 16 | 3268920 |
| 17 | 8885999 |
| 18 | 24154826 |
| 19 | 65659826 |
| 20 | 178482140 |