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 | 4 |
| 1 | 58 |
| 2 | 988 |
| 3 | 17560 |
| 4 | 315184 |
| 5 | 5669728 |
| 6 | 102040768 |
| 7 | 1836676480 |
| 8 | 33059947264 |
| 9 | 595078133248 |
| 10 | 10711402728448 |
| 11 | 192805234432000 |
| 12 | 3470494161055744 |
| 13 | 62468894664122368 |
| 14 | 1124440103014678528 |
| 15 | 20239921850506117120 |
| 16 | 364318593294077722624 |
| 17 | 6557734679233269465088 |
| 18 | 118039224225958332203008 |