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 | 3 |
| 2 | 6 |
| 3 | 23 |
| 4 | 50 |
| 5 | 131 |
| 6 | 294 |
| 7 | 687 |
| 8 | 1530 |
| 9 | 3419 |
| 10 | 7502 |
| 11 | 16391 |
| 12 | 35490 |
| 13 | 76467 |
| 14 | 163830 |
| 15 | 349535 |
| 16 | 742730 |
| 17 | 1572875 |
| 18 | 3320478 |
| 19 | 6990519 |
| 20 | 14680050 |
| 21 | 30758243 |
| 22 | 64312646 |
| 23 | 134217743 |
| 24 | 279620250 |
| 25 | 581610171 |
| 26 | 1207959534 |
| 27 | 2505397607 |
| 28 | 5189752130 |
| 29 | 10737418259 |
| 30 | 22190664342 |