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) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 31 |
| 4 | 486 |
| 5 | 15381 |
| 6 | 978768 |
| 7 | 124918731 |
| 8 | 31932406170 |
| 9 | 16337382642945 |
| 10 | 16723323142761060 |
| 11 | 34243057328337866295 |
| 12 | 140246638967945496322350 |
| 13 | 1148847521944847479468879725 |
| 14 | 18822284044001939139425413111800 |
| 15 | 616761496621711735518439444437389475 |