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 | 3 |
| 2 | 6 |
| 3 | 12 |
| 4 | 26 |
| 5 | 62 |
| 6 | 157 |
| 7 | 409 |
| 8 | 1079 |
| 9 | 2863 |
| 10 | 7617 |
| 11 | 20299 |
| 12 | 54202 |
| 13 | 145134 |
| 14 | 390048 |
| 15 | 1052840 |
| 16 | 2855633 |
| 17 | 7784909 |
| 18 | 21333806 |
| 19 | 58769738 |
| 20 | 162735221 |
| 21 | 452890963 |
| 22 | 1266501060 |
| 23 | 3558037366 |
| 24 | 10038873751 |
| 25 | 28437746721 |
| 26 | 80854303650 |
| 27 | 230659891380 |