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 | 3 |
| 2 | 12 |
| 3 | 45 |
| 4 | 171 |
| 5 | 619 |
| 6 | 2560 |
| 7 | 10774 |
| 8 | 46708 |
| 9 | 202635 |
| 10 | 904603 |
| 11 | 4073767 |
| 12 | 18604618 |
| 13 | 85445767 |
| 14 | 395944114 |
| 15 | 1837763447 |
| 16 | 8600149593 |