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 | 3 |
| 2 | 9 |
| 3 | 27 |
| 4 | 91 |
| 5 | 293 |
| 6 | 959 |
| 7 | 3121 |
| 8 | 10171 |
| 9 | 33141 |
| 10 | 107985 |
| 11 | 351855 |
| 12 | 1146471 |
| 13 | 3735623 |
| 14 | 12172023 |
| 15 | 39660897 |
| 16 | 129229689 |
| 17 | 421077529 |
| 18 | 1372024391 |
| 19 | 4470556607 |
| 20 | 14566706329 |
| 21 | 47463649813 |
| 22 | 154653907527 |
| 23 | 503918919165 |
| 24 | 1641951898617 |
| 25 | 5350079020329 |