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 | 114 |
| 3 | 1068 |
| 4 | 10011 |
| 5 | 93840 |
| 6 | 879624 |
| 7 | 8245296 |
| 8 | 77288598 |
| 9 | 724477008 |
| 10 | 6791000856 |
| 11 | 63656530320 |
| 12 | 596694646092 |
| 13 | 5593212493440 |
| 14 | 52428869944896 |
| 15 | 491450379709824 |
| 16 | 4606688566257048 |
| 17 | 43181530471120320 |
| 18 | 404768967341615520 |
| 19 | 3794166513675844032 |
| 20 | 35565225338407615152 |