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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 2 |
| 6 | 5 |
| 7 | 10 |
| 8 | 17 |
| 9 | 27 |
| 10 | 68 |
| 11 | 107 |
| 12 | 217 |
| 13 | 420 |
| 14 | 884 |
| 15 | 1761 |
| 16 | 3679 |
| 17 | 7469 |
| 18 | 15437 |
| 19 | 31396 |
| 20 | 64369 |