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 | 6 |
| 3 | 31 |
| 4 | 156 |
| 5 | 784 |
| 6 | 3962 |
| 7 | 20173 |
| 8 | 103522 |
| 9 | 535294 |
| 10 | 2787700 |
| 11 | 14613710 |
| 12 | 77072816 |
| 13 | 408737760 |
| 14 | 2178631156 |
| 15 | 11666175215 |
| 16 | 62734622764 |
| 17 | 338660977020 |
| 18 | 1834690352066 |
| 19 | 9971834477972 |
| 20 | 54361287536706 |
| 21 | 297170702049966 |
| 22 | 1628670524735842 |