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 | 5 |
| 3 | 18 |
| 4 | 53 |
| 5 | 140 |
| 6 | 347 |
| 7 | 826 |
| 8 | 1913 |
| 9 | 4344 |
| 10 | 9719 |
| 11 | 21494 |
| 12 | 47093 |
| 13 | 102388 |
| 14 | 221171 |
| 15 | 475122 |
| 16 | 1015793 |
| 17 | 2162672 |
| 18 | 4587503 |
| 19 | 9699310 |
| 20 | 20447213 |
| 21 | 42991596 |
| 22 | 90177515 |
| 23 | 188743658 |
| 24 | 394264553 |
| 25 | 822083560 |
| 26 | 1711276007 |
| 27 | 3556769766 |
| 28 | 7381975013 |
| 29 | 15300820964 |
| 30 | 31675383779 |