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 | 5 |
| 2 | 51 |
| 3 | 618 |
| 4 | 8043 |
| 5 | 108753 |
| 6 | 1505652 |
| 7 | 21181632 |
| 8 | 301445115 |
| 9 | 4327546335 |
| 10 | 62550664827 |
| 11 | 909065484726 |
| 12 | 13271032349844 |
| 13 | 194464001709708 |
| 14 | 2858582670411768 |
| 15 | 42135099729748512 |
| 16 | 622533141544186779 |
| 17 | 9216768941364987195 |
| 18 | 136706015987753749593 |