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 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 16 |
| 5 | 103 |
| 6 | 799 |
| 7 | 7286 |
| 8 | 71094 |
| 9 | 729974 |
| 10 | 7743818 |
| 11 | 84307887 |
| 12 | 937002302 |
| 13 | 10595117272 |
| 14 | 121568251909 |
| 15 | 1412555701804 |
| 16 | 16594126114458 |
| 17 | 196829590326284 |
| 18 | 2354703777373055 |
| 19 | 28385225424840078 |
| 20 | 344524656398655124 |
| 21 | 4207569734885041198 |
| 22 | 51674558137433627724 |