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 | 2 |
| 3 | 8 |
| 4 | 49 |
| 5 | 402 |
| 6 | 4144 |
| 7 | 51515 |
| 8 | 750348 |
| 9 | 12537204 |
| 10 | 236424087 |
| 11 | 4967735896 |
| 12 | 115102258660 |
| 13 | 2915655255385 |
| 14 | 80164472149454 |
| 15 | 2377679022913612 |
| 16 | 75674858155603353 |
| 17 | 2572626389524849478 |
| 18 | 93040490884813025684 |
| 19 | 3566833833735159397963 |
| 20 | 144485408698878208399296 |