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 | 1 |
| 2 | 5 |
| 3 | 51 |
| 4 | 809 |
| 5 | 17575 |
| 6 | 486460 |
| 7 | 16384260 |
| 8 | 650574249 |
| 9 | 29762953831 |
| 10 | 1541719486081 |
| 11 | 89201504309927 |
| 12 | 5702038255950404 |
| 13 | 399105271607867940 |
| 14 | 30359621863987241460 |
| 15 | 2494052823831234355340 |
| 16 | 220067051126228849480649 |