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A284446 Sum_{d|n, d = 5 mod 7} d. 6
0, 0, 0, 0, 5, 0, 0, 0, 0, 5, 0, 12, 0, 0, 5, 0, 0, 0, 19, 5, 0, 0, 0, 12, 5, 26, 0, 0, 0, 5, 0, 0, 33, 0, 5, 12, 0, 19, 0, 45, 0, 0, 0, 0, 5, 0, 47, 12, 0, 5, 0, 26, 0, 54, 5, 0, 19, 0, 0, 17, 61, 0, 0, 0, 5, 33, 0, 68, 0, 5, 0, 12, 0, 0, 80, 19, 0, 26, 0, 45, 0, 82 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

FORMULA

G.f.: Sum_{k>=0} (5+7k) x^(5+7k)/(1-x^(5+7k)). - Robert Israel, Mar 27 2017

MAPLE

f:= n -> convert(select(t -> t mod 7 = 5, numtheory:-divisors(n)), `+`):

map(f, [$1..1000]); # Robert Israel, Mar 27 2017

MATHEMATICA

Table[DivisorSum[n, # &, Mod[#, 7] == 5 &], {n, 82}] (* Giovanni Resta, Mar 27 2017 *)

PROG

(PARI) for(n=1, 82, print1(sumdiv(n, d, if(Mod(d, 7)==5, d, 0)), ", ")) \\ Indranil Ghosh, Mar 27 2017

CROSSREFS

Cf. A109707.

Cf. Sum_{d|n, d=k mod 7} d: A284099 (k=1), A284443 (k=2), A284444 (k=3), A284445 (k=4), this sequence (k=5), A284105 (k=6).

Sequence in context: A336881 A324323 A005078 * A270030 A284104 A260911

Adjacent sequences:  A284443 A284444 A284445 * A284447 A284448 A284449

KEYWORD

nonn

AUTHOR

Seiichi Manyama, Mar 27 2017

STATUS

approved

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Last modified August 10 02:26 EDT 2020. Contains 336366 sequences. (Running on oeis4.)