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%I #9 May 19 2018 12:38:20
%S 1,2,2,2,2,4,2,2,2,4,2,5,2,4,4,2,2,5,2,5,4,4,2,6,2,4,2,5,2,8,2,2,4,4,
%T 4,6,2,4,4,6,2,8,2,5,5,4,2,7,2,5,4,5,2,6,4,6,4,4,2,11,2,4,5,2,4,8,2,5,
%U 4,8,2,8,2,4,5,5,4,8,2,7,2,4,2,11,4,4
%N Number of divisors of n that are either 1 or not a perfect power.
%C First differs from A183095 at a(80) = 8, A183095(80) = 7.
%F a(n) = A183096(n) + 1.
%e The a(72) = 8 divisors of 72 that are either 1 or not a perfect power are {1, 2, 3, 6, 12, 18, 24, 72}. Missing are {4, 8, 9, 36}.
%t Table[DivisorSum[n,Boole[GCD@@FactorInteger[#][[All,2]]==1]&],{n,100}]
%o (PARI) a(n) = sumdiv(n, d, !ispower(d)); \\ _Michel Marcus_, May 19 2018
%Y Cf. A000005, A001597, A007916, A091050, A183096, A304326, A304362, A304653, A304779, A304819, A304820.
%K nonn
%O 1,2
%A _Gus Wiseman_, May 18 2018