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 | 4 |
| 2 | 7 |
| 3 | 15 |
| 4 | 34 |
| 5 | 79 |
| 6 | 184 |
| 7 | 426 |
| 8 | 984 |
| 9 | 2274 |
| 10 | 5258 |
| 11 | 12159 |
| 12 | 28117 |
| 13 | 65018 |
| 14 | 150347 |
| 15 | 347661 |
| 16 | 803931 |
| 17 | 1859013 |
| 18 | 4298789 |
| 19 | 9940535 |
| 20 | 22986529 |
| 21 | 53154136 |
| 22 | 122913828 |
| 23 | 284226412 |
| 24 | 657246261 |
| 25 | 1519818815 |
| 26 | 3514434954 |
| 27 | 8126793100 |
| 28 | 18792428087 |
| 29 | 43455684079 |