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A071327 Sum of prime squares dividing n. 2
0, 0, 0, 4, 0, 0, 0, 4, 9, 0, 0, 4, 0, 0, 0, 4, 0, 9, 0, 4, 0, 0, 0, 4, 25, 0, 9, 4, 0, 0, 0, 4, 0, 0, 0, 13, 0, 0, 0, 4, 0, 0, 0, 4, 9, 0, 0, 4, 49, 25, 0, 4, 0, 9, 0, 4, 0, 0, 0, 4, 0, 0, 9, 4, 0, 0, 0, 4, 0, 0, 0, 13, 0, 0, 25, 4, 0, 0, 0, 4, 9, 0, 0, 4, 0, 0, 0, 4, 0, 9, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

FORMULA

a(n) = Sum_{d|n} A010052(d)*A010051(A000196(d))*d. - Antti Karttunen, Nov 18 2017

MATHEMATICA

Array[DivisorSum[#, # &, PrimeQ@ Sqrt@ # &] &, 91] (* Michael De Vlieger, Nov 18 2017 *)

PROG

(PARI) A071327(n) = { my(r); sumdiv(n, d, (issquare(d, &r)&&isprime(r)) * d); } \\ Antti Karttunen, Nov 19 2017

CROSSREFS

Cf. A010051, A010052, A063958, A056170, A071326.

Sequence in context: A028598 A272618 A265397 * A071326 A284103 A151674

Adjacent sequences:  A071324 A071325 A071326 * A071328 A071329 A071330

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, May 18 2002

STATUS

approved

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Last modified February 23 10:59 EST 2018. Contains 299536 sequences. (Running on oeis4.)