# Computed 2017-12-16 in GP/PARI CALCULATOR Version 2.9.2 (released) amd64 running mingw (x86-64/GMP-6.1.2 kernel) 64-bit version, compiled: Mar 22 2017, gcc version 4.9.1 (GCC), threading engine: single # with the following PARI-program: # # A091853(n) = { my(digs=digits(n),nd=length(digs),k,p,s = Set([])); for(j=0,nd!-1, p=numtoperm(nd, j); if(1