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 | 1 |
| 2 | 5 |
| 3 | 37 |
| 4 | 352 |
| 5 | 4315 |
| 6 | 64534 |
| 7 | 1140538 |
| 8 | 23256803 |
| 9 | 537441241 |
| 10 | 13880477010 |
| 11 | 396218076727 |
| 12 | 12386985584175 |
| 13 | 420923890579261 |
| 14 | 15447592770126359 |
| 15 | 608903758014263548 |
| 16 | 25656487848259583960 |
| 17 | 1150788495459483630199 |
| 18 | 54745172171004903538414 |
| 19 | 2753138362843249502728559 |
| 20 | 145939080567682948612742851 |