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 | 3 |
| 2 | 435 |
| 3 | 1855 |
| 4 | 1678635 |
| 5 | 8178093 |
| 6 | 831557727 |
| 7 | 4362807735 |
| 8 | 26663516457435 |
| 9 | 146862472576105 |
| 10 | 13439367283090749 |
| 11 | 76661183599555737 |
| 12 | 54390019021528255975 |
| 13 | 318658997759516188425 |
| 14 | 27581665786275463543575 |
| 15 | 165068987339858265879975 |
| 16 | 7173478080571052213369487675 |