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 | 1 |
| 2 | 4 |
| 3 | 27 |
| 4 | 268 |
| 5 | 3585 |
| 6 | 60846 |
| 7 | 1255471 |
| 8 | 30535912 |
| 9 | 855688833 |
| 10 | 27148954330 |
| 11 | 962037575631 |
| 12 | 37659124454700 |
| 13 | 1613921425656865 |
| 14 | 75156944627712598 |
| 15 | 3778932799275876495 |
| 16 | 204039148080188427856 |
| 17 | 11774630933193827543553 |