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 | 12 |
| 2 | 88 |
| 3 | 636 |
| 4 | 4720 |
| 5 | 35892 |
| 6 | 277768 |
| 7 | 2175276 |
| 8 | 17167840 |
| 9 | 136170852 |
| 10 | 1083507448 |
| 11 | 8638762716 |
| 12 | 68963617360 |
| 13 | 550976517012 |
| 14 | 4404150026728 |
| 15 | 35214889666956 |
| 16 | 281627564601280 |
| 17 | 2252562753138372 |
| 18 | 18018213206747608 |
| 19 | 144134261562183996 |