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A284326 Sum of the divisors of n that are not divisible by 6. 7
1, 3, 4, 7, 6, 6, 8, 15, 13, 18, 12, 10, 14, 24, 24, 31, 18, 15, 20, 42, 32, 36, 24, 18, 31, 42, 40, 56, 30, 36, 32, 63, 48, 54, 48, 19, 38, 60, 56, 90, 42, 48, 44, 84, 78, 72, 48, 34, 57, 93, 72, 98, 54, 42, 72, 120, 80, 90, 60, 60, 62, 96, 104, 127, 84, 72, 68 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Seiichi Manyama, Table of n, a(n) for n = 1..10000

FORMULA

G.f.: Sum_{k>=1} k*x^k/(1 - x^k) - 6*k*x^(6*k)/(1 - x^(6*k)). - Ilya Gutkovskiy, Mar 25 2017

MATHEMATICA

Table[Sum[Boole[Mod[d, 6]>0] d , {d, Divisors[n]}], {n, 100}] (* Indranil Ghosh, Mar 25 2017 *)

PROG

(PARI) for(n=1, 100, print1(sumdiv(n, d, ((d%6)>0)*d), ", ")) \\ Indranil Ghosh, Mar 25 2017

(Python)

from sympy import divisors

print [sum([i for i in divisors(n) if i%6>0]) for n in xrange(1, 101)] # Indranil Ghosh, Mar 25 2017

CROSSREFS

Cf. Sum of the divisors of n that are not divisible by k: A046913 (k=3), A046897 (k=4), A116073 (k=5), this sequence (k=6), A113957 (k=7), A284341 (k=8), A116607 (k=9), A284344 (k=10).

Sequence in context: A023888 A222085 A187793 * A117553 A290270 A168275

Adjacent sequences:  A284323 A284324 A284325 * A284327 A284328 A284329

KEYWORD

nonn

AUTHOR

Seiichi Manyama, Mar 25 2017

STATUS

approved

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Last modified April 24 10:11 EDT 2019. Contains 322420 sequences. (Running on oeis4.)