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) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 44 |
| 5 | 186 |
| 6 | 814 |
| 7 | 3648 |
| 8 | 16611 |
| 9 | 76437 |
| 10 | 354112 |
| 11 | 1647344 |
| 12 | 7682237 |
| 13 | 35873310 |
| 14 | 167625690 |
| 15 | 783470179 |
| 16 | 3662035980 |
| 17 | 17115684065 |
| 18 | 79986841677 |
| 19 | 373759118882 |
| 20 | 1746296080947 |