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) |
|---|---|
| 1 | 3 |
| 2 | 21 |
| 3 | 143 |
| 4 | 1061 |
| 5 | 8366 |
| 6 | 68932 |
| 7 | 585881 |
| 8 | 5094722 |
| 9 | 45074595 |
| 10 | 404185377 |
| 11 | 3663479699 |
| 12 | 33498077106 |
| 13 | 308548877876 |
| 14 | 2859703657128 |
| 15 | 26646019345842 |
| 16 | 249434445759050 |
| 17 | 2344494354096166 |
| 18 | 22116172789221197 |
| 19 | 209301155352811190 |
| 20 | 1986521422431963549 |
| 21 | 18904049485198437478 |
| 22 | 180323870540071281301 |
| 23 | 1723847795281971132487 |
| 24 | 16512536418951055856540 |
| 25 | 158463448213030472998711 |