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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 7 |
| 6 | 14 |
| 7 | 36 |
| 8 | 83 |
| 9 | 212 |
| 10 | 532 |
| 11 | 1379 |
| 12 | 3577 |
| 13 | 9444 |
| 14 | 25019 |
| 15 | 66943 |
| 16 | 179994 |
| 17 | 487031 |
| 18 | 1323706 |
| 19 | 3614622 |
| 20 | 9907911 |