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) |
|---|---|
| 0 | 3 |
| 1 | 6 |
| 2 | 13 |
| 3 | 31 |
| 4 | 78 |
| 5 | 201 |
| 6 | 523 |
| 7 | 1366 |
| 8 | 3573 |
| 9 | 9351 |
| 10 | 24478 |
| 11 | 64081 |
| 12 | 167763 |
| 13 | 439206 |
| 14 | 1149853 |
| 15 | 3010351 |
| 16 | 7881198 |
| 17 | 20633241 |
| 18 | 54018523 |
| 19 | 141422326 |
| 20 | 370248453 |
| 21 | 969323031 |
| 22 | 2537720638 |
| 23 | 6643838881 |
| 24 | 17393796003 |
| 25 | 45537549126 |
| 26 | 119218851373 |
| 27 | 312119004991 |
| 28 | 817138163598 |