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 | 45 |
| 3 | 2565 |
| 4 | 161595 |
| 5 | 10762227 |
| 6 | 742593663 |
| 7 | 52511980455 |
| 8 | 3780862592760 |
| 9 | 276002969271480 |
| 10 | 20369019132235224 |
| 11 | 1516566060845513496 |
| 12 | 113742454563413512200 |
| 13 | 8583180609746819651400 |
| 14 | 651095557682223033556200 |
| 15 | 49613481495385395156982440 |
| 16 | 3795431334396982729509156660 |