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 | 2 |
| 3 | 6 |
| 4 | 16 |
| 5 | 44 |
| 6 | 120 |
| 7 | 329 |
| 8 | 904 |
| 9 | 2493 |
| 10 | 6898 |
| 11 | 19151 |
| 12 | 53340 |
| 13 | 149019 |
| 14 | 417522 |
| 15 | 1172979 |
| 16 | 3303696 |
| 17 | 9326931 |
| 18 | 26390070 |
| 19 | 74824584 |
| 20 | 212565864 |
| 21 | 604972998 |
| 22 | 1724739940 |
| 23 | 4925066567 |
| 24 | 14085122376 |
| 25 | 40339596755 |
| 26 | 115688495806 |
| 27 | 332203673142 |
| 28 | 955090832416 |
| 29 | 2749055259956 |
| 30 | 7921280088744 |