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 | 5 |
| 3 | 51 |
| 4 | 293 |
| 5 | 1383 |
| 6 | 6017 |
| 7 | 25315 |
| 8 | 104941 |
| 9 | 431775 |
| 10 | 1768377 |
| 11 | 7218555 |
| 12 | 29388325 |
| 13 | 119381239 |
| 14 | 484031537 |
| 15 | 1959295251 |
| 16 | 7919693789 |
| 17 | 31972642767 |
| 18 | 128937189161 |
| 19 | 519476334379 |
| 20 | 2091181293589 |
| 21 | 8412008183079 |
| 22 | 33816433653921 |
| 23 | 135865503379395 |
| 24 | 545598121631437 |
| 25 | 2190000348372223 |