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.
Fibonacci[n+1]-(2*n+3), {n,0,40}] (* _G. C. Greubel's wiki page.
Fibonacci[n+1]-(2*n+3), {n,0,40}] (* _G. C. Greubel has authored 0 sequences.