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) |
|---|---|
| 0 | 19 |
| 1 | 57 |
| 2 | 171 |
| 3 | 513 |
| 4 | 1539 |
| 5 | 4617 |
| 6 | 13851 |
| 7 | 41553 |
| 8 | 124659 |
| 9 | 373977 |
| 10 | 1121931 |
| 11 | 3365793 |
| 12 | 10097379 |
| 13 | 30292137 |
| 14 | 90876411 |
| 15 | 272629233 |
| 16 | 817887699 |
| 17 | 2453663097 |
| 18 | 7360989291 |
| 19 | 22082967873 |
| 20 | 66248903619 |
| 21 | 198746710857 |
| 22 | 596240132571 |
| 23 | 1788720397713 |
| 24 | 5366161193139 |
| 25 | 16098483579417 |