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 | 2 |
| 3 | 6 |
| 4 | 12 |
| 5 | 36 |
| 6 | 174 |
| 7 | 500 |
| 8 | 2052 |
| 9 | 12112 |
| 10 | 65092 |
| 11 | 407882 |
| 12 | 2954798 |
| 13 | 20568796 |
| 14 | 157579774 |
| 15 | 1346294112 |
| 16 | 11580692142 |
| 17 | 110130002110 |
| 18 | 1145065547108 |