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 | 6 |
| 2 | 48 |
| 3 | 468 |
| 4 | 5340 |
| 5 | 69516 |
| 6 | 1014348 |
| 7 | 16372908 |
| 8 | 289366860 |
| 9 | 5553635436 |
| 10 | 114964523148 |
| 11 | 2552305112748 |
| 12 | 60474398655180 |
| 13 | 1522843616043756 |
| 14 | 40605864407444748 |
| 15 | 1142786353739186988 |
| 16 | 33848016050071188300 |
| 17 | 1052381222812017946476 |
| 18 | 34266937867683980363148 |
| 19 | 1166071764343727862515628 |