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 | 5 |
| 2 | 25 |
| 3 | 125 |
| 4 | 545 |
| 5 | 1943 |
| 6 | 6797 |
| 7 | 23627 |
| 8 | 83391 |
| 9 | 298239 |
| 10 | 1073743 |
| 11 | 3873051 |
| 12 | 13959617 |
| 13 | 50261845 |
| 14 | 180829983 |
| 15 | 650385801 |
| 16 | 2339156205 |
| 17 | 8413500735 |
| 18 | 30263904639 |
| 19 | 108865370619 |
| 20 | 391615337877 |
| 21 | 1408733302733 |
| 22 | 5067520822187 |
| 23 | 18228904185829 |