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 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 2 |
| 5 | 7 |
| 6 | 23 |
| 7 | 78 |
| 8 | 311 |
| 9 | 1297 |
| 10 | 6200 |
| 11 | 31747 |
| 12 | 178703 |
| 13 | 1070388 |
| 14 | 6842898 |
| 15 | 46158435 |
| 16 | 327718768 |
| 17 | 2437732593 |
| 18 | 18948528721 |
| 19 | 153498234770 |
| 20 | 1293122838953 |
| 21 | 11306474635818 |
| 22 | 102425551817363 |
| 23 | 959826751122645 |
| 24 | 9290811889272509 |
| 25 | 92771812680385087 |
| 26 | 954447072777977556 |