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 | 45 |
| 3 | 2850 |
| 4 | 206625 |
| 5 | 16116750 |
| 6 | 1316201250 |
| 7 | 110936962500 |
| 8 | 9568313015625 |
| 9 | 839885253593750 |
| 10 | 74749787569843750 |
| 11 | 6727480881285937500 |
| 12 | 611079513383472656250 |
| 13 | 55937278532794804687500 |
| 14 | 5154220664807521289062500 |
| 15 | 477624448272163639453125000 |
| 16 | 44478776745345238924072265625 |