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 | 1 |
| 2 | 6 |
| 3 | 72 |
| 4 | 1289 |
| 5 | 29889 |
| 6 | 831174 |
| 7 | 26455564 |
| 8 | 934766625 |
| 9 | 35896627737 |
| 10 | 1475461220832 |
| 11 | 64175536953702 |
| 12 | 2928055871469177 |
| 13 | 139180794974903769 |
| 14 | 6854741942660442918 |
| 15 | 348244986517582367748 |
| 16 | 18183302860592129336633 |
| 17 | 972820066413029570529513 |
| 18 | 53192593416458179801289034 |