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 | 31 |
| 3 | 643 |
| 4 | 20421 |
| 5 | 873806 |
| 6 | 46994011 |
| 7 | 3042431715 |
| 8 | 230249448841 |
| 9 | 19940350062394 |
| 10 | 1944516598602711 |
| 11 | 210829412453667998 |
| 12 | 25156743053019602701 |
| 13 | 3275876521195372322892 |
| 14 | 462262670054775645538099 |
| 15 | 70264375447526610838701091 |