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A125613 Sum of the squares of the quadratic residues of prime(n). 6
1, 1, 17, 21, 132, 351, 816, 874, 1104, 4031, 3286, 8473, 11726, 11868, 11233, 24857, 28143, 38247, 46766, 40754, 66722, 65017, 83249, 120150, 156364, 173013, 152955, 184147, 218763, 245436, 297053, 327500, 437030, 413803, 556217, 488334, 652335 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

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 residues of 7=prime(4) are 1, 2 and 4. Hence a(4)=1^2 + 2^2 + 4^2=21.

PROG

(PARI) vector(37, n, p=prime(n); t=1; for(i=2, (p-1)/2, t+=((i^2)%p)^2); t)

CROSSREFS

Cf. A076409, A076410, A125613-A125618.

Sequence in context: A060875 A138600 A050845 * A147052 A147132 A146840

Adjacent sequences:  A125610 A125611 A125612 * A125614 A125615 A125616

KEYWORD

easy,nonn

AUTHOR

Nick Hobson Nov 30 2006

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.