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 | 1 |
| 1 | 21 |
| 2 | 171 |
| 3 | 745 |
| 4 | 2418 |
| 5 | 7587 |
| 6 | 20510 |
| 7 | 51351 |
| 8 | 122715 |
| 9 | 277384 |
| 10 | 598812 |
| 11 | 1255761 |
| 12 | 2543973 |
| 13 | 5011725 |
| 14 | 9653013 |
| 15 | 18176040 |
| 16 | 33535032 |
| 17 | 60831648 |
| 18 | 108490390 |
| 19 | 190557015 |
| 20 | 330174837 |
| 21 | 564626278 |
| 22 | 953857104 |
| 23 | 1593681480 |
| 24 | 2634409140 |
| 25 | 4311592119 |
| 26 | 6991502688 |
| 27 | 11237020682 |
| 28 | 17909802270 |