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 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 32 |
| 4 | 734 |
| 5 | 28994 |
| 6 | 1752046 |
| 7 | 150262104 |
| 8 | 17356844088 |
| 9 | 2597710341600 |
| 10 | 488957612319984 |
| 11 | 113044488306692304 |
| 12 | 31490845086661001664 |
| 13 | 10403092187976909854640 |
| 14 | 4021236906890850070201488 |
| 15 | 1798052050351216209712206336 |
| 16 | 920859156623446912386646303104 |