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 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 14 |
| 5 | 85 |
| 6 | 616 |
| 7 | 5072 |
| 8 | 46013 |
| 9 | 450739 |
| 10 | 4702265 |
| 11 | 51731956 |
| 12 | 595874703 |
| 13 | 7147366614 |
| 14 | 88905147730 |
| 15 | 1143097097833 |
| 16 | 15152617826426 |
| 17 | 206646826047563 |
| 18 | 2894398418226395 |
| 19 | 41577147999077079 |
| 20 | 611779190051375147 |
| 21 | 9211548488261257610 |
| 22 | 141802624561414800815 |