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 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 24 |
| 6 | 72 |
| 7 | 231 |
| 8 | 764 |
| 9 | 2574 |
| 10 | 8840 |
| 11 | 30796 |
| 12 | 108528 |
| 13 | 386308 |
| 14 | 1386756 |
| 15 | 5014575 |
| 16 | 18249120 |
| 17 | 66786738 |
| 18 | 245642760 |
| 19 | 907513530 |
| 20 | 3366215688 |
| 21 | 12531502620 |
| 22 | 46805032560 |
| 23 | 175341580596 |
| 24 | 658674458208 |
| 25 | 2480584898700 |
| 26 | 9363748625972 |