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 | -1 |
| 2 | -3 |
| 3 | -5 |
| 4 | -7 |
| 5 | -21 |
| 6 | -92 |
| 7 | -209 |
| 8 | -415 |
| 9 | -947 |
| 10 | -1403 |
| 11 | -8484 |
| 12 | -26675 |
| 13 | -70708 |
| 14 | -205919 |
| 15 | -737729 |
| 16 | -2162013 |
| 17 | -4741957 |
| 18 | -13992966 |
| 19 | -77928220 |
| 20 | -122866869 |
| 21 | -374649610 |
| 22 | -1334960954 |
| 23 | -5317831008 |
| 24 | -9896721062 |
| 25 | -38014073661 |