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 | 20 |
| 3 | 1301 |
| 4 | 202840 |
| 5 | 61889101 |
| 6 | 32676403052 |
| 7 | 27418828825961 |
| 8 | 34361404413755056 |
| 9 | 61335081309931829401 |
| 10 | 150221740688275657957940 |
| 11 | 489799709605132718770274141 |
| 12 | 2073641570051429601078643837960 |
| 13 | 11163099186064084100687107863253381 |