# A355827 for range 1 .. 65537 computed by Antti Karttunen, 2022-07-19
# in GP/PARI CALCULATOR Version 2.9.4 (released) amd64 running linux (x86-64/GMP-6.1.2 kernel) 64-bit version, compiled: Dec 19 2017, gcc version 7.3.0 (Ubuntu 7.3.0-1ubuntu1), threading engine: pthread
# with the following program:
#
# ispow2(n) = (n && !bitand(n,n-1));
# A302777(n) = ispow2(isprimepower(n));
# memoA355827 = Map();
# A355827(n) = if(1==n,1,my(v); if(mapisdefined(memoA355827,n,&v), v, v = -sumdiv(n,d,if(d