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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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Last modified December 9 20:00 EST 2016. Contains 278986 sequences.