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 | 13 |
| 2 | 103 |
| 3 | 625 |
| 4 | 3151 |
| 5 | 14053 |
| 6 | 58975 |
| 7 | 242461 |
| 8 | 989527 |
| 9 | 4017157 |
| 10 | 16245775 |
| 11 | 65514541 |
| 12 | 263652487 |
| 13 | 1059392917 |
| 14 | 4251920575 |
| 15 | 17050729021 |
| 16 | 68332056247 |
| 17 | 273715645477 |
| 18 | 1096024843375 |
| 19 | 4387586157901 |
| 20 | 17560804984807 |
| 21 | 70274600998837 |