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 | 1 |
| 2 | 8 |
| 3 | 71 |
| 4 | 1072 |
| 5 | 20161 |
| 6 | 476288 |
| 7 | 13315751 |
| 8 | 432387712 |
| 9 | 15959926081 |
| 10 | 660372282368 |
| 11 | 30265936565831 |
| 12 | 1522069164439552 |
| 13 | 83327826089289601 |
| 14 | 4933286107483701248 |
| 15 | 314052936209639958311 |
| 16 | 21392225375507849838592 |
| 17 | 1552501782546292090638721 |
| 18 | 119588747474281844162428928 |