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A071326 Sum of squares > 1 dividing n. 2
0, 0, 0, 4, 0, 0, 0, 4, 9, 0, 0, 4, 0, 0, 0, 20, 0, 9, 0, 4, 0, 0, 0, 4, 25, 0, 9, 4, 0, 0, 0, 20, 0, 0, 0, 49, 0, 0, 0, 4, 0, 0, 0, 4, 9, 0, 0, 20, 49, 25, 0, 4, 0, 9, 0, 4, 0, 0, 0, 4, 0, 0, 9, 84, 0, 0, 0, 4, 0, 0, 0, 49, 0, 0, 25, 4, 0, 0, 0, 20, 90, 0, 0, 4, 0, 0, 0, 4, 0, 9, 0, 4, 0, 0, 0, 20, 0, 49, 9, 129 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16384

FORMULA

a(n) = A035316(n)-1.

Sum_{d|n, d>1} A010052(d). - Antti Karttunen, Nov 17 2017

MATHEMATICA

Array[DivisorSum[#, # &, IntegerQ@ Sqrt@ # &] - 1 &, 100] (* Michael De Vlieger, Nov 17 2017 *)

PROG

(PARI) A071326(n) = sumdiv(n, d, (d>1)*issquare(d)*d); \\ Antti Karttunen, Nov 17 2017

CROSSREFS

Cf. A000203, A010052, A071325, A071327.

One less than A035316.

Sequence in context: A272618 A265397 A071327 * A284103 A151674 A297968

Adjacent sequences:  A071323 A071324 A071325 * A071327 A071328 A071329

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, May 18 2002

EXTENSIONS

More terms from Antti Karttunen, Nov 17 2017

STATUS

approved

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Last modified October 15 13:01 EDT 2018. Contains 316236 sequences. (Running on oeis4.)