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) |
|---|---|
| 4 | 1 |
| 5 | 11 |
| 6 | 79 |
| 7 | 471 |
| 8 | 2535 |
| 9 | 12809 |
| 10 | 62067 |
| 11 | 292085 |
| 12 | 1345718 |
| 13 | 6102780 |
| 14 | 27343148 |
| 15 | 121359692 |
| 16 | 534632836 |
| 17 | 2341151646 |
| 18 | 10201950700 |
| 19 | 44278673806 |
| 20 | 191540714294 |
| 21 | 826265471868 |
| 22 | 3555992623850 |
| 23 | 15273547250820 |
| 24 | 65491352071266 |
| 25 | 280412963707416 |