A121278 Number of distinct integers of the form (x^n + y^n) mod n^2.

1, 3, 5, 3, 13, 9, 19, 5, 15, 15, 51, 9, 73, 30, 65, 9, 113, 21, 163, 9, 25, 63, 265, 15, 65, 57, 45, 30, 281, 45, 391, 17, 255, 123, 247, 21, 577, 165, 65, 15, 841, 27, 757, 63, 195, 234, 1105, 27, 133, 75

Offset

1,2

Comments

It is enough to take x,y from {0,1,...,n-1}. Therefore a(n)<=n*(n+1)/2.

Links

Table of n, a(n) for n=1..50.

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 }

Crossrefs

Sequence in context: A336806 A023583 A266603 * A023587 A172003 A244801

Adjacent sequences: A121275 A121276 A121277 * A121279 A121280 A121281

Keyword

nonn

Author

Max Alekseyev, Aug 23 2006

Status

approved