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 | 1 |
| 2 | 4 |
| 3 | 54 |
| 4 | 2246 |
| 5 | 164950 |
| 6 | 18423144 |
| 7 | 2905943328 |
| 8 | 615376173184 |
| 9 | 168483518571798 |
| 10 | 57926238289970076 |
| 11 | 24434798429947993054 |
| 12 | 12408968034664788792008 |
| 13 | 7468360391233437715595634 |
| 14 | 5256695596753687250025931048 |
| 15 | 4278271932454694494134007741950 |
| 16 | 3986830862631720154048770746485900 |