OFFSET
1,2
COMMENTS
It is enough to take x,y from {0,1,...,n-1}. Therefore a(n)<=n*(n+1)/2.
PROG
(PARI) { a(n) = my(S, t); S=Set(); for(x=0, n-1, for(y=x, n-1, t=lift(Mod(x, n^2)^n+Mod(y, n^2)^n); S=setunion(S, [t]); ); ); #S }
(PARI) a(n) = #setbinop((x, y)->Mod(x, n^2)^n+Mod(y, n^2)^n, [0..n-1]); \\ Michel Marcus, Oct 16 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
Max Alekseyev, Aug 23 2006
EXTENSIONS
More terms from Michel Marcus, Oct 16 2023
STATUS
approved