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 A125617 Sum of the squares of the quadratic nonresidues of prime(n). 2
 0, 4, 13, 70, 253, 299, 680, 1235, 2691, 3683, 6169, 7733, 10414, 13717, 22278, 23373, 38586, 35563, 51255, 76041, 60298, 96222, 103916, 110894, 143172, 165337, 206000, 218494, 206991, 229164, 377698, 413305, 410726, 471766, 535357, 647941, 625331 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS For all n > 3, prime(n) divides a(n). REFERENCES D. M. Burton, Elementary Number Theory, McGraw-Hill, Sixth Edition (2007), p. 185. LINKS N. Hobson, Table of n, a(n) for n = 1..1000 N. Hobson, Home page (listed in lieu of email address) EXAMPLE The quadratic nonresidues of 7=prime(4) are 3, 5 and 6. Hence a(4)=3^2 + 5^2 + 6^2=70. PROG (PARI) vector(37, n, p=prime(n); t=1; for(i=2, (p-1)/2, t+=((i^2)%p)^2); p*(p-1)*(2*p-1)/6-t) CROSSREFS Cf. A076409, A076410, A125613-A125618. Sequence in context: A009221 A009239 A042277 * A197969 A121452 A249165 Adjacent sequences:  A125614 A125615 A125616 * A125618 A125619 A125620 KEYWORD easy,nonn AUTHOR Nick Hobson Nov 30 2006 STATUS approved

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