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 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 71 |
| 9 | 253 |
| 10 | 673 |
| 11 | 1585 |
| 12 | 38149 |
| 13 | 277707 |
| 14 | 1402831 |
| 15 | 5923503 |
| 16 | 85577571 |
| 17 | 937629969 |
| 18 | 7475614341 |
| 19 | 48939413477 |
| 20 | 587610659505 |
| 21 | 7906296686903 |
| 22 | 87384175023995 |
| 23 | 804959532778571 |
| 24 | 9729015122635103 |
| 25 | 144711323234918941 |
| 26 | 2009073351016603121 |