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 | 1 |
| 2 | 3 |
| 3 | 19 |
| 4 | 107 |
| 5 | 641 |
| 6 | 51103 |
| 7 | 1897879 |
| 8 | 7860361 |
| 9 | 505249081 |
| 10 | 40865339743 |
| 11 | 1355547261301 |
| 12 | 244350418462637 |
| 13 | 34907820791828741 |
| 14 | 1949845703291363567 |
| 15 | 1136592473036395958917 |
| 16 | 31690844708764028510969 |
| 17 | 2681369908698254192692979 |
| 18 | 768531714669026186032238737 |