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 | 52 |
| 2 | 2705 |
| 3 | 140712 |
| 4 | 7319729 |
| 5 | 380766620 |
| 6 | 19807183969 |
| 7 | 1030354333008 |
| 8 | 53598232500385 |
| 9 | 2788138444353028 |
| 10 | 145036797338857841 |
| 11 | 7544701600064960760 |
| 12 | 392469520000716817361 |
| 13 | 20415959741637339463532 |
| 14 | 1062022376085142368921025 |
| 15 | 55245579516169040523356832 |