The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
For n = 2 the first 16 terms of the Möbius sequence are (1,-1,-1,0,-1,1,-1,0,0,1,-1,0,-1,1,1,0) which contains all 9 possible length-2 blocks; no shorter prefix does.