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 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 11 |
| 4 | 30 |
| 5 | 83 |
| 6 | 236 |
| 7 | 687 |
| 8 | 2026 |
| 9 | 6023 |
| 10 | 17984 |
| 11 | 53819 |
| 12 | 161254 |
| 13 | 483451 |
| 14 | 1449876 |
| 15 | 4348903 |
| 16 | 13045602 |
| 17 | 39135119 |
| 18 | 117402792 |
| 19 | 352204467 |
| 20 | 1056607454 |