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 | 100 |
| 2 | 4950 |
| 3 | 161700 |
| 4 | 3921225 |
| 5 | 75287520 |
| 6 | 1192052400 |
| 7 | 16007560800 |
| 8 | 186087894300 |
| 9 | 1902231808400 |
| 10 | 17310309456440 |
| 11 | 141629804643600 |
| 12 | 1050421051106700 |
| 13 | 7110542499799200 |
| 14 | 44186942677323600 |
| 15 | 253338471349988640 |
| 16 | 1345860629046814650 |
| 17 | 6650134872937201800 |