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 | 5 |
| 3 | 19 |
| 4 | 49 |
| 5 | 193 |
| 6 | 685 |
| 7 | 2721 |
| 8 | 12341 |
| 9 | 49171 |
| 10 | 271801 |
| 11 | 1084483 |
| 12 | 7073725 |
| 13 | 28245729 |
| 14 | 212385209 |
| 15 | 848456353 |
| 16 | 7226001865 |
| 17 | 28875761731 |
| 18 | 274743964621 |
| 19 | 1098127402131 |
| 20 | 11544775603241 |
| 21 | 46150226651233 |
| 22 | 531276670190245 |
| 23 | 2124008553358849 |
| 24 | 26573182030311229 |
| 25 | 106246577894593683 |
| 26 | 1435390805853694145 |