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 | 7 |
| 2 | 23 |
| 3 | 79 |
| 4 | 269 |
| 5 | 839 |
| 6 | 2477 |
| 7 | 7477 |
| 8 | 22397 |
| 9 | 66533 |
| 10 | 197453 |
| 11 | 592393 |
| 12 | 1772033 |
| 13 | 5317217 |
| 14 | 15955019 |
| 15 | 47860361 |
| 16 | 143540597 |
| 17 | 430579631 |
| 18 | 1291494329 |
| 19 | 3874347863 |
| 20 | 11622575663 |
| 21 | 34869569509 |
| 22 | 104608356781 |
| 23 | 313820413861 |
| 24 | 941454837811 |
| 25 | 2824364840663 |
| 26 | 8473084264373 |
| 27 | 25419236780191 |
| 28 | 76257724291547 |