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 | 19 |
| 2 | 189 |
| 3 | 1311 |
| 4 | 7124 |
| 5 | 32300 |
| 6 | 127091 |
| 7 | 445721 |
| 8 | 1420364 |
| 9 | 4172476 |
| 10 | 11426240 |
| 11 | 29429784 |
| 12 | 71808030 |
| 13 | 166970290 |
| 14 | 371826581 |
| 15 | 796341623 |
| 16 | 1646167391 |
| 17 | 3294638285 |
| 18 | 6401307860 |
| 19 | 12102626403 |
| 20 | 22312161567 |
| 21 | 40184022241 |
| 22 | 70815180079 |
| 23 | 122291797486 |
| 24 | 207223385049 |
| 25 | 344958892116 |