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 | 0 |
| 2 | 2 |
| 3 | 3 |
| 4 | 19 |
| 5 | 39 |
| 6 | 200 |
| 7 | 615 |
| 8 | 2849 |
| 9 | 11174 |
| 10 | 52377 |
| 11 | 239269 |
| 12 | 1191090 |
| 13 | 6041975 |
| 14 | 32275288 |
| 15 | 177797719 |
| 16 | 1017833092 |
| 17 | 6014562272 |
| 18 | 36717301665 |
| 19 | 230947360981 |
| 20 | 1495562098099 |
| 21 | 9956230757240 |
| 22 | 68070158777759 |
| 23 | 477439197541792 |
| 24 | 3432259679880648 |
| 25 | 25267209686664449 |