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 | 15 |
| 2 | 43 |
| 3 | 99 |
| 4 | 263 |
| 5 | 695 |
| 6 | 1891 |
| 7 | 5195 |
| 8 | 14431 |
| 9 | 40383 |
| 10 | 113723 |
| 11 | 321875 |
| 12 | 914903 |
| 13 | 2609895 |
| 14 | 7468147 |
| 15 | 21427259 |
| 16 | 61622671 |
| 17 | 177588815 |
| 18 | 512734699 |
| 19 | 1482818915 |
| 20 | 4294677703 |
| 21 | 12455435063 |
| 22 | 36167638627 |
| 23 | 105140060555 |
| 24 | 305958613855 |
| 25 | 891185076095 |