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 | 0 |
| 1 | 2 |
| 2 | 6 |
| 3 | 17 |
| 4 | 46 |
| 5 | 127 |
| 6 | 346 |
| 7 | 942 |
| 8 | 2561 |
| 9 | 6961 |
| 10 | 18923 |
| 11 | 51440 |
| 12 | 139829 |
| 13 | 380095 |
| 14 | 1033206 |
| 15 | 2808546 |
| 16 | 7634421 |
| 17 | 20752508 |
| 18 | 56411165 |
| 19 | 153341447 |
| 20 | 416825269 |
| 21 | 1133048555 |
| 22 | 3079945300 |
| 23 | 8372159341 |
| 24 | 22757888603 |
| 25 | 61862355045 |
| 26 | 168159315586 |
| 27 | 457104411844 |
| 28 | 1242538616426 |