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%I #16 Jan 09 2022 01:05:22
%S 6,10,14,15,21,22,24,26,30,33,34,35,38,39,40,42,46,51,54,55,56,57,58,
%T 60,62,65,66,69,70,74,77,78,82,84,85,86,87,88,90,91,93,94,95,96,102,
%U 104,105,106,110,111,114,115,118,119,120,122,123,126,129,130,132,133,134,135,136,138,140,141,142,143,145,146,150
%N Numbers of the form c * m^2, where m > 0 and c is composite and squarefree.
%C Subsequence of A048943. According to _Gerard P. Michon_, one of the criteria for N to belong to A048943 is that it has at least two prime factors with odd multiplicities. By definition, the composite factor c in any term of A229153 conforms to this criterion.
%C From a(1) to a(63), identical to the given terms of A119847, except for the single term a(55) = 120.
%H Chris Boyd, <a href="/A229153/b229153.txt">Table of n, a(n) for n = 1..10000</a>
%o (PARI) iscomposite(n)={if(!isprime(n)&&n!=1,return(1));}
%o test(n)={if(iscomposite(core(n)),return(1));}
%o for(n=1,200,if(test(n)==1,print1(n",")))
%o (PARI) lista(nn) = {for(n=1,nn, if(!ispseudoprime(core(n)) && !issquare(n), print1(n, ", ")));} \\ _Altug Alkan_, Feb 04 2016
%o (PARI) list(lim)=my(v=List()); forsquarefree(c=6,lim\=1, if(#c[2]~ > 1, for(m=1,sqrtint(lim\c[1]), listput(v, c[1]*m^2)))); Set(v) \\ _Charles R Greathouse IV_, Jan 09 2022
%Y Complement of A265640.
%Y Cf. A048943, A229125.
%K nonn
%O 1,1
%A _Chris Boyd_, Sep 15 2013