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 | 2 |
| 2 | 20 |
| 3 | 226 |
| 4 | 2696 |
| 5 | 33138 |
| 6 | 415164 |
| 7 | 5270850 |
| 8 | 67576208 |
| 9 | 872918690 |
| 10 | 11343392228 |
| 11 | 148120453538 |
| 12 | 1941910368280 |
| 13 | 25545250484498 |
| 14 | 337010368660876 |
| 15 | 4457154741645954 |
| 16 | 59076597464830240 |
| 17 | 784518823873380930 |
| 18 | 10435840680299248052 |
| 19 | 139030100339736030306 |
| 20 | 1854730153008453738408 |