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 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 7 |
| 5 | 19 |
| 6 | 71 |
| 7 | 219 |
| 8 | 759 |
| 9 | 2697 |
| 10 | 12395 |
| 11 | 47477 |
| 12 | 231950 |
| 13 | 1040116 |
| 14 | 4851742 |
| 15 | 26690821 |
| 16 | 131478031 |
| 17 | 736418510 |
| 18 | 4262619682 |
| 19 | 24680045903 |
| 20 | 145629814329 |
| 21 | 935900941506 |
| 22 | 5778263418232 |
| 23 | 37626913475878 |
| 24 | 257550263109475 |
| 25 | 1782180357952449 |
| 26 | 12526035635331581 |