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 | 8 |
| 3 | 53 |
| 4 | 326 |
| 5 | 1997 |
| 6 | 12370 |
| 7 | 77513 |
| 8 | 490306 |
| 9 | 3124541 |
| 10 | 20030000 |
| 11 | 129024469 |
| 12 | 834451788 |
| 13 | 5414950283 |
| 14 | 35240152706 |
| 15 | 229911617041 |
| 16 | 1503232609082 |
| 17 | 9847379391133 |
| 18 | 64617565719052 |
| 19 | 424655979547781 |
| 20 | 2794563003870310 |
| 21 | 18412956934908669 |
| 22 | 121455445321173578 |