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 | 21 |
| 2 | 23 |
| 3 | 40 |
| 4 | 161 |
| 5 | 361 |
| 6 | 741 |
| 7 | 1592 |
| 8 | 3469 |
| 9 | 7416 |
| 10 | 15880 |
| 11 | 34193 |
| 12 | 73457 |
| 13 | 157645 |
| 14 | 338676 |
| 15 | 727589 |
| 16 | 1562584 |
| 17 | 3356196 |
| 18 | 7209121 |
| 19 | 15484337 |
| 20 | 33258365 |
| 21 | 71436088 |
| 22 | 153437805 |
| 23 | 329568008 |
| 24 | 707878984 |
| 25 | 1520453793 |
| 26 | 3265780153 |
| 27 | 7014565013 |
| 28 | 15066579716 |