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 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 24 |
| 6 | 62 |
| 7 | 155 |
| 8 | 396 |
| 9 | 992 |
| 10 | 2504 |
| 11 | 6228 |
| 12 | 15512 |
| 13 | 38220 |
| 14 | 94059 |
| 15 | 229498 |
| 16 | 558642 |
| 17 | 1350384 |
| 18 | 3255138 |
| 19 | 7801327 |
| 20 | 18642118 |
| 21 | 44329833 |
| 22 | 105111283 |
| 23 | 248184255 |
| 24 | 584396849 |
| 25 | 1371048495 |
| 26 | 3208318247 |
| 27 | 7483522231 |
| 28 | 17413665881 |
| 29 | 40405120865 |
| 30 | 93543352492 |