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 | 8 |
| 3 | 25 |
| 4 | 100 |
| 5 | 550 |
| 6 | 4224 |
| 7 | 42135 |
| 8 | 516383 |
| 9 | 7373984 |
| 10 | 118573680 |
| 11 | 2103205868 |
| 12 | 40634185593 |
| 13 | 847871397697 |
| 14 | 18987149095396 |
| 15 | 454032821689310 |
| 16 | 11544329612486760 |
| 17 | 310964453836199398 |
| 18 | 8845303172513782781 |