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%I #60 May 27 2023 13:05:28
%S 1,3,1,1,1,3,1,9,10,3,1,13,1,3,1,1,1,30,1,1,1,3,1,33,1,3,1,1,1,3,1,1,
%T 1,3,1,46,1,3,1,49,1,3,1,1,10,3,1,1,1,3,1,1,1,3,1,65,1,3,1,73,1,3,10,
%U 1,1,3,1,1,1,3,1,90,1,3,1,1,1,3,1,81,1,3,1,97,1,3,1,97
%N Sum of the refactorable unitary divisors of n.
%F a(n) = Sum_{d|n, tau(d)|d, gcd(d,n/d)=1} d.
%t a[n_] := DivisorSum[n, # &, CoprimeQ[#, n/#] && Divisible[#, DivisorSigma[0, #]] &]; Array[a, 100]
%Y Cf. A034444, A336041, A363298.
%K nonn,easy
%O 1,2
%A _Wesley Ivan Hurt_, May 27 2023