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 | 9 |
| 2 | 79 |
| 3 | 697 |
| 4 | 6196 |
| 5 | 55455 |
| 6 | 499178 |
| 7 | 4514873 |
| 8 | 40999516 |
| 9 | 373585604 |
| 10 | 3414035527 |
| 11 | 31278197839 |
| 12 | 287191809724 |
| 13 | 2642070371194 |
| 14 | 24347999094724 |
| 15 | 224723513577529 |
| 16 | 2076978797223820 |
| 17 | 19220104372823340 |
| 18 | 178061257422521452 |
| 19 | 1651314042800498052 |
| 20 | 15328459501269535952 |