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A162296 Sum of divisors of n that have a square factor. 5
0, 0, 0, 4, 0, 0, 0, 12, 9, 0, 0, 16, 0, 0, 0, 28, 0, 27, 0, 24, 0, 0, 0, 48, 25, 0, 36, 32, 0, 0, 0, 60, 0, 0, 0, 79, 0, 0, 0, 72, 0, 0, 0, 48, 54, 0, 0, 112, 49, 75, 0, 56, 0, 108, 0, 96, 0, 0, 0, 96, 0, 0, 72, 124, 0, 0, 0, 72, 0, 0, 0, 183, 0, 0, 100, 80, 0, 0, 0, 168, 117, 0, 0, 128, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Note that 1 does not have a square factor. - Antti Karttunen, Nov 20 2017

LINKS

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

Index entries for sequences related to sums of divisors

FORMULA

a(n) + A048250(n) = A000203(n). - Antti Karttunen, Nov 20 2017

EXAMPLE

a(8) = 12 = 4 + 8.

MATHEMATICA

Array[DivisorSum[#, # &, # (1 - MoebiusMu[#]^2) == # &] &, 86] (* Michael De Vlieger, Nov 20 2017 *)

PROG

(PARI) a(n)=sumdiv(n, d, d*(1-moebius(d)^2)); v=vector(300, n, a(n))

CROSSREFS

Cf. A000203, A005117, A048250.

Sequence in context: A126849 A284117 A183099 * A169773 A236380 A298825

Adjacent sequences:  A162293 A162294 A162295 * A162297 A162298 A162299

KEYWORD

easy,nonn

AUTHOR

Joerg Arndt, Jun 30 2009

STATUS

approved

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Last modified November 19 11:20 EST 2018. Contains 317351 sequences. (Running on oeis4.)