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 | 10 |
| 2 | 44 |
| 3 | 160 |
| 4 | 672 |
| 5 | 2860 |
| 6 | 12482 |
| 7 | 55198 |
| 8 | 246712 |
| 9 | 1111372 |
| 10 | 5037174 |
| 11 | 22940158 |
| 12 | 104870790 |
| 13 | 480863770 |
| 14 | 2210197754 |
| 15 | 10178143810 |
| 16 | 46942294232 |
| 17 | 216761695840 |
| 18 | 1001878336772 |
| 19 | 4634206919128 |
| 20 | 21448419453382 |
| 21 | 99316222901062 |