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 A165951 a(n) = (Sum of the quadratic non-residues of prime(n) - Sum of the quadratic residues of prime(n)) / prime(n) 5

%I

%S 0,0,0,1,1,0,0,1,3,0,3,0,0,1,5,0,3,0,1,7,0,5,3,0,0,0,5,3,0,0,5,5,0,3,

%T 0,7,0,1,11,0,5,0,13,0,0,9,3,7,5,0,0,15,0,7,0,13,0,11,0,0,3,0,3,19,0,

%U 0,3,0,5,0,0,19,9,0,3,17,0,0,0,0,9,0,21,0,15,5,0,0,0,7,7,25,7,9,3,21,0,0

%N a(n) = (Sum of the quadratic non-residues of prime(n) - Sum of the quadratic residues of prime(n)) / prime(n)

%C Also, a(n) = (sum (floor (j^2/p(n))), j = 1:p(n)-1) - floor ((p(n)-2)(p(n)-1)/3) for n >= 3.

%H C. H. Gribble, <a href="/A165951/b165951.txt">Table of n, a(n) for n=1,..., 348513 (i.e. for primes < 5x10^6)</a>.

%Y a(3:) = A125616 - A076410.

%K nonn

%O 1,9

%A _Christopher Hunt Gribble_, Oct 01 2009

%E a(1:2) added and cross-reference section modified by _Christopher Hunt Gribble_, Oct 07 2009

%E Comment corrected by _Christopher Hunt Gribble_, Oct 17 2009

%E Comment corrected by _Christopher Hunt Gribble_, Oct 29 2009

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Last modified March 25 07:42 EDT 2023. Contains 361511 sequences. (Running on oeis4.)