cp's OEIS Frontend

A304327 Number of ways to write n as a product of a perfect power and a squarefree number.

%I A304327 #10 Jul 30 2018 13:47:37
%S A304327 1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,2,1,1,2,1,1,1,1,2,1,1,
%T A304327 1,1,1,1,1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,2,1,2,1,1,1,1,1,1,1,2,1,1,1,1,
%U A304327 1,1,1,1,1,1,1,1,1,1,1,2,2,1,1,1,1,1,1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,2,1
%N A304327 Number of ways to write n as a product of a perfect power and a squarefree number.
%C A304327 First term greater than 2 is a(746496) = 3.
%H A304327 Antti Karttunen, <a href="/A304327/b304327.txt">Table of n, a(n) for n = 1..65537</a>
%e A304327 The a(746496) = 3 ways are 12^5*3, 72^3*2, 864^2*1.
%t A304327 Table[Length[Select[Divisors[n],(#===1||GCD@@FactorInteger[#][[All,2]]>1)&&SquareFreeQ[n/#]&]],{n,100}]
%o A304327 (PARI) A304327(n) = sumdiv(n,d,issquarefree(n/d)*((1==d)||ispower(d))); \\ _Antti Karttunen_, Jul 29 2018
%Y A304327 Cf. A000961, A001055, A001597, A005117, A007916, A034444, A091050, A183096, A203025, A246549, A303386, A304326, A304328.
%K A304327 nonn
%O A304327 1,8
%A A304327 _Gus Wiseman_, May 10 2018
%E A304327 More terms from _Antti Karttunen_, Jul 29 2018