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 | 12 |
| 2 | 132 |
| 3 | 1392 |
| 4 | 14292 |
| 5 | 144000 |
| 6 | 1430592 |
| 7 | 14057280 |
| 8 | 136914804 |
| 9 | 1323843936 |
| 10 | 12722294736 |
| 11 | 121625850240 |
| 12 | 1157512059936 |
| 13 | 10972654675200 |
| 14 | 103654156958208 |
| 15 | 976153872234240 |
| 16 | 9167420099612340 |