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>=1} is the INVERT transform of (u(n))'s wiki page.
{n>=1} is the INVERT transform of (u(n)) has authored 0 sequences.