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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 25 |
| 5 | 2020 |
| 6 | 82115 |
| 7 | 2401910 |
| 8 | 58089465 |
| 9 | 1245331920 |
| 10 | 24625121455 |
| 11 | 460316430970 |
| 12 | 8266174350005 |
| 13 | 144171200793620 |
| 14 | 2461016066613195 |
| 15 | 41343340015862430 |
| 16 | 686274244801356145 |
| 17 | 11289648429330100120 |