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 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 2 |
| 6 | 22 |
| 7 | 226 |
| 8 | 2198 |
| 9 | 22120 |
| 10 | 236968 |
| 11 | 2732268 |
| 12 | 33940644 |
| 13 | 453148422 |
| 14 | 6480322210 |
| 15 | 98907371822 |
| 16 | 1605581578202 |
| 17 | 27631315113916 |
| 18 | 502618772515748 |
| 19 | 9637245372790760 |
| 20 | 194291040277517688 |
| 21 | 4109014039030693578 |
| 22 | 90968013940830446574 |
| 23 | 2104072961763468757082 |