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%I #14 Jun 30 2022 05:57:21
%S 0,2,0,2,0,8,0,2,0,12,0,8,0,16,0,2,0,8,0,12,0,24,0,8,0,28,0,16,0,48,0,
%T 2,0,36,0,8,0,40,0,12,0,64,0,24,0,48,0,8,0,12,0,28,0,8,0,16,0,60,0,48,
%U 0,64,0,2,0,96,0,36,0,96,0,8,0,76,0,40,0,112,0,12,0,84,0,64,0,88,0,24,0,48,0,48,0,96
%N Sum of even squarefree divisors of n.
%H Antti Karttunen, <a href="/A319697/b319697.txt">Table of n, a(n) for n = 1..20000</a>
%F a(n) = Sum_{d|n} A059841(d)*A008966(d)*d.
%F a(n) = A048250(n) - A206787(n).
%t Table[Total[Select[Divisors[n],EvenQ[#]&&SquareFreeQ[#]&]],{n,100}] (* _Harvey P. Dale_, May 18 2019 *)
%t f[2, e_] := 2; f[p_, e_] := p + 1; a[n_] := If[OddQ[n], 0, Times @@ f @@@ FactorInteger[n]]; Array[a, 100] (* _Amiram Eldar_, Jun 30 2022 *)
%o (PARI) A319697(n) = sumdiv(n, d, (!(d%2))*issquarefree(d)*d);
%Y Cf. A048250, A146076, A183063, A206787, A319698.
%K nonn
%O 1,2
%A _Antti Karttunen_, Oct 31 2018
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