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 | 6 |
| 3 | 47 |
| 4 | 199 |
| 5 | 661 |
| 6 | 1954 |
| 7 | 5442 |
| 8 | 14696 |
| 9 | 39065 |
| 10 | 103025 |
| 11 | 270655 |
| 12 | 709716 |
| 13 | 1859412 |
| 14 | 4869594 |
| 15 | 12750611 |
| 16 | 33383659 |
| 17 | 87401977 |
| 18 | 228824086 |
| 19 | 599072310 |
| 20 | 1568395100 |
| 21 | 4106115485 |
| 22 | 10749954101 |
| 23 | 28143749827 |
| 24 | 73681298664 |
| 25 | 192900149736 |
| 26 | 505019154414 |
| 27 | 1322157317687 |