# Computed 2017-10-09 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 based on Reinhard Zumkeller's formula: # # A010056(n) = { my(k=n^2); k+=(k+1)<<2; (issquare(k) || (n>0 && issquare(k-8))) }; \\ This function from _Charles R Greathouse IV_, Jul 30 2012 # A293435(n) = sumdiv(n,d,(d