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) |
|---|---|
| 1 | 139968 |
| 2 | 995328 |
| 3 | 63700992 |
| 4 | 4076863488 |
| 5 | 17714700000 |
| 6 | 82012500000 |
| 7 | 98802571392 |
| 8 | 174960000000 |
| 9 | 445240556352 |
| 10 | 641194278912 |
| 11 | 889223142528 |
| 12 | 1059917571072 |
| 13 | 1594323000000 |
| 14 | 1663012435968 |
| 15 | 2348273369088 |
| 16 | 3333709317312 |
| 17 | 5717741400000 |
| 18 | 16260080320512 |
| 19 | 19144761127488 |
| 20 | 28697814000000 |