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 | 7 |
| 2 | 41 |
| 3 | 247 |
| 4 | 1481 |
| 5 | 8887 |
| 6 | 53321 |
| 7 | 319927 |
| 8 | 1919561 |
| 9 | 11517367 |
| 10 | 69104201 |
| 11 | 414625207 |
| 12 | 2487751241 |
| 13 | 14926507447 |
| 14 | 89559044681 |
| 15 | 537354268087 |
| 16 | 3224125608521 |
| 17 | 19344753651127 |
| 18 | 116068521906761 |
| 19 | 696411131440567 |
| 20 | 4178466788643401 |