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 | 3 |
| 4 | 16 |
| 5 | 30 |
| 6 | 480 |
| 7 | 840 |
| 8 | 22080 |
| 9 | 68040 |
| 10 | 1088640 |
| 11 | 3991680 |
| 12 | 259459200 |
| 13 | 518918400 |
| 14 | 16605388800 |
| 15 | 163459296000 |
| 16 | 10353459916800 |
| 17 | 22230464256000 |
| 18 | 1867358997504000 |
| 19 | 6758061133824000 |
| 20 | 648773868847104000 |
| 21 | 5474029518397440000 |
| 22 | 122618261212102656000 |