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 | 165 |
| 1 | 4455 |
| 2 | 57915 |
| 3 | 495495 |
| 4 | 3185325 |
| 5 | 16563690 |
| 6 | 73002930 |
| 7 | 281582730 |
| 8 | 972740340 |
| 9 | 3062330700 |
| 10 | 8904315420 |
| 11 | 24168856140 |
| 12 | 61764854580 |
| 13 | 149660993790 |
| 14 | 345855237750 |
| 15 | 766005304350 |
| 16 | 1632800780325 |
| 17 | 3361648665375 |
| 18 | 6705510829875 |
| 19 | 12993932469375 |
| 20 | 24518985616125 |