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 | 3 |
| 2 | 33 |
| 3 | 367 |
| 4 | 4533 |
| 5 | 58971 |
| 6 | 794805 |
| 7 | 10983819 |
| 8 | 154653081 |
| 9 | 2209251319 |
| 10 | 31925528217 |
| 11 | 465708778407 |
| 12 | 6846750893929 |
| 13 | 101325729466071 |
| 14 | 1508015866093929 |
| 15 | 22553429144856471 |
| 16 | 338744206097695629 |
| 17 | 5106973783924992771 |
| 18 | 77251106929381097229 |
| 19 | 1172036566162209342771 |