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 | 2 |
| 2 | 11 |
| 3 | 90 |
| 4 | 952 |
| 5 | 12203 |
| 6 | 182677 |
| 7 | 3118314 |
| 8 | 59688447 |
| 9 | 1265193199 |
| 10 | 29408221404 |
| 11 | 743677646836 |
| 12 | 20325564686926 |
| 13 | 597051775012306 |
| 14 | 18758388926380409 |
| 15 | 627712133246362442 |
| 16 | 22288938527631882996 |
| 17 | 837033514431748421053 |
| 18 | 33146037056721682537319 |
| 19 | 1380365444443138768970878 |