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 | 6 |
| 2 | 84 |
| 3 | 1638 |
| 4 | 38976 |
| 5 | 1068480 |
| 6 | 32716992 |
| 7 | 1098069504 |
| 8 | 39896236800 |
| 9 | 1555603999488 |
| 10 | 64678765165056 |
| 11 | 2853714891138048 |
| 12 | 133101200708356608 |
| 13 | 6542154022577467392 |
| 14 | 337978986519657627648 |
| 15 | 18310837206705702672384 |