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 | 6 |
| 2 | 26 |
| 3 | 85 |
| 4 | 252 |
| 5 | 734 |
| 6 | 2149 |
| 7 | 6321 |
| 8 | 18673 |
| 9 | 55373 |
| 10 | 164729 |
| 11 | 491332 |
| 12 | 1468446 |
| 13 | 4395388 |
| 14 | 13170815 |
| 15 | 39497285 |
| 16 | 118511408 |
| 17 | 355728667 |
| 18 | 1068051097 |
| 19 | 3207330581 |
| 20 | 9632722080 |
| 21 | 28932821313 |
| 22 | 86907496260 |
| 23 | 261060029437 |
| 24 | 784214341324 |
| 25 | 2355790958452 |