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%I #14 Jul 14 2024 08:53:08
%S 16,48,64,80,81,112,144,162,176,192,208,240,256,272,304,320,324,336,
%T 368,400,405,432,448,464,496,512,528,560,567,576,592,624,625,648,656,
%U 688,704,720,729,752,768,784,810,816,832,848,880,891,912,944,960,976,1008
%N Numbers whose maximum exponent in their prime factorization is a composite number.
%C Subsequence of A322448 and first differs from it at n = 138: A322448(138) = 2592 = 2^5 * 3^4 is not a term of this sequence.
%C The asymptotic density of this sequence is d = Sum_{k composite} (1/zeta(k+1) - 1/zeta(k)) = 0.05296279266796920306... . The asymptotic density of this sequence within the nonsquarefree numbers (A013929) is d / (1 - 1/zeta(2)) = 0.13508404411123191108... .
%H Amiram Eldar, <a href="/A374588/b374588.txt">Table of n, a(n) for n = 1..10000</a>
%p filter:= proc(n) local m;
%p m:= max(ifactors(n)[2][..,2]);
%p m > 1 and not isprime(m)
%p end proc:
%p select(filter, [$1..10000]); # _Robert Israel_, Jul 14 2024
%t Select[Range[1200], CompositeQ[Max[FactorInteger[#][[;; , 2]]]] &]
%o (PARI) iscomposite(n) = n > 1 && !isprime(n);
%o is(n) = n > 1 && iscomposite(vecmax(factor(n)[, 2]));
%Y Cf. A002808, A013661, A051903, A229099.
%Y Complement of A074661 within A013929.
%Y Subsequence of A322448 and A322449 \ {1}.
%Y Similar sequences: A368714, A369937, A369938, A369939, A374589, A374590.
%K nonn,easy
%O 1,1
%A _Amiram Eldar_, Jul 12 2024