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 | 9 |
| 5 | 339 |
| 6 | 3606 |
| 7 | 24474 |
| 8 | 121077 |
| 9 | 475353 |
| 10 | 1568712 |
| 11 | 4524540 |
| 12 | 11722134 |
| 13 | 27828138 |
| 14 | 61442460 |
| 15 | 127616970 |
| 16 | 251577939 |
| 17 | 474068124 |
| 18 | 858822579 |
| 19 | 1502804622 |
| 20 | 2549955858 |
| 21 | 4209357693 |
| 22 | 6778862319 |
| 23 | 10675429650 |
| 24 | 16473604089 |
| 25 | 24953782251 |
| 26 | 37162160802 |
| 27 | 54484513344 |
| 28 | 78736227726 |