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 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 7 |
| 5 | 19 |
| 6 | 41 |
| 7 | 751 |
| 8 | 989 |
| 9 | 2857 |
| 10 | 16067 |
| 11 | 434293 |
| 12 | 1364651 |
| 13 | 8181904909 |
| 14 | 90241897 |
| 15 | 5044289 |
| 16 | 15043611773 |
| 17 | 5026792806787 |
| 18 | 203732352169 |
| 19 | 69028763155644023 |
| 20 | 1145302367137 |
| 21 | 1022779523247467 |
| 22 | 396760150748100749 |
| 23 | 750218743980105669781 |
| 24 | 35200969735190093 |