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 | 2 |
| 3 | 6 |
| 4 | 24 |
| 5 | 120 |
| 6 | 720 |
| 7 | 5040 |
| 8 | 630 |
| 9 | 5670 |
| 10 | 56700 |
| 11 | 623700 |
| 12 | 7484400 |
| 13 | 97297200 |
| 14 | 1362160800 |
| 15 | 28028000 |
| 16 | 7007000 |
| 17 | 119119000 |
| 18 | 2144142000 |
| 19 | 40738698000 |
| 20 | 12730843125 |
| 21 | 267347705625 |
| 22 | 5881649523750 |
| 23 | 135277939046250 |
| 24 | 3246670537110000 |
| 25 | 5194672859376 |
| 26 | 135061494343776 |