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 | 4 |
| 2 | 10 |
| 3 | 26 |
| 4 | 69 |
| 5 | 175 |
| 6 | 432 |
| 7 | 1076 |
| 8 | 2671 |
| 9 | 6627 |
| 10 | 16421 |
| 11 | 40695 |
| 12 | 100886 |
| 13 | 250093 |
| 14 | 619947 |
| 15 | 1536810 |
| 16 | 3809790 |
| 17 | 9444489 |
| 18 | 23412999 |
| 19 | 58041252 |
| 20 | 143885484 |
| 21 | 356695266 |
| 22 | 884255363 |
| 23 | 2192088651 |
| 24 | 5434237397 |
| 25 | 13471597487 |
| 26 | 33396394603 |
| 27 | 82790419927 |
| 28 | 205239329905 |