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 | 3 |
| 3 | 7 |
| 4 | 43 |
| 5 | 57 |
| 6 | 307 |
| 7 | 1068 |
| 8 | 2943 |
| 9 | 12943 |
| 10 | 45807 |
| 11 | 110443 |
| 12 | 670807 |
| 13 | 2733307 |
| 14 | 25670807 |
| 15 | 113561432 |
| 16 | 123327057 |
| 17 | 657922943 |
| 18 | 17213170807 |
| 19 | 7200891693 |
| 20 | 148802454193 |
| 21 | 1120482141693 |