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 | 4 |
| 2 | 4 |
| 3 | 33 |
| 4 | 259 |
| 5 | 3127 |
| 6 | 46661 |
| 7 | 823549 |
| 8 | 16777219 |
| 9 | 387420493 |
| 10 | 10000000003 |
| 11 | 285311670617 |
| 12 | 8916100448287 |
| 13 | 302875106592259 |
| 14 | 11112006825558019 |
| 15 | 437893890380859379 |
| 16 | 18446744073709551617 |
| 17 | 827240261886336764197 |
| 18 | 39346408075296537575443 |
| 19 | 1978419655660313589124007 |