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 | 4 |
| 3 | 11 |
| 4 | 33 |
| 5 | 96 |
| 6 | 281 |
| 7 | 821 |
| 8 | 2400 |
| 9 | 7015 |
| 10 | 20505 |
| 11 | 59936 |
| 12 | 175193 |
| 13 | 512089 |
| 14 | 1496836 |
| 15 | 4375251 |
| 16 | 12788857 |
| 17 | 37381824 |
| 18 | 109267057 |
| 19 | 319387565 |
| 20 | 933569728 |
| 21 | 2728823951 |
| 22 | 7976351345 |
| 23 | 23314871872 |
| 24 | 68149361393 |