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 | 1 |
| 3 | 2 |
| 4 | 12 |
| 5 | 35 |
| 6 | 206 |
| 7 | 780 |
| 8 | 4949 |
| 9 | 22686 |
| 10 | 156972 |
| 11 | 837333 |
| 12 | 6301550 |
| 13 | 38122554 |
| 14 | 310279615 |
| 15 | 2090641920 |
| 16 | 18293310174 |
| 17 | 135445359397 |
| 18 | 1267153412532 |
| 19 | 10202944645270 |
| 20 | 101557600812015 |
| 21 | 881921432827544 |
| 22 | 9299499328238110 |
| 23 | 86508104545175503 |
| 24 | 962663031508255416 |