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 | 3 |
| 2 | 24 |
| 3 | 255 |
| 4 | 3102 |
| 5 | 40854 |
| 6 | 566934 |
| 7 | 8164263 |
| 8 | 120864390 |
| 9 | 1827982362 |
| 10 | 28122626760 |
| 11 | 438720097638 |
| 12 | 6923868098820 |
| 13 | 110346550539780 |
| 14 | 1773394661610258 |
| 15 | 28707809007278775 |
| 16 | 467677404522668742 |
| 17 | 7661583171651546786 |
| 18 | 126137791939032756960 |
| 19 | 2085923447593966281378 |