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%I #12 Jan 05 2024 02:55:57
%S 4,12,16,18,20,24,27,28,36,44,48,50,52,54,60,68,72,76,80,84,90,92,98,
%T 100,108,112,116,120,124,126,132,135,140,144,148,150,156,160,164,168,
%U 172,176,180,188,189,192,196,198,204,208,212,216,220,228,234,236,240,242,244,252,256,260,264,268,270,272
%N Nonsquarefree numbers k such that k is divisible by the maximal exponent in the prime factorization of k.
%C The asymptotic density of this sequence is A336065 - A059956 = 0.24103009315... . - _Amiram Eldar_, Jan 05 2024
%H Harvey P. Dale, <a href="/A144976/b144976.txt">Table of n, a(n) for n = 1..1000</a>
%F {A013929(i): A051903(A013929(i)) | A013929(i)}. - _R. J. Mathar_, Oct 24 2008
%p A051903 := proc(n) local a,ifs,p,e; a := 1 ; max( seq(op(2,p),p=ifactors(n)[2]) ); end: isA013929 := proc(n) RETURN( not isprime(n) and A051903(n) > 1 ) ; end: isA144976 := proc(n) RETURN( isA013929(n) and (n mod A051903(n)) = 0 ); end: for n from 4 to 400 do if isA144976(n) then printf("%d,",n) ; fi; od: # _R. J. Mathar_, Oct 24 2008
%t Select[Range[300],!SquareFreeQ[#]&&Divisible[#,Max[FactorInteger[#][[All,2]]]]&] (* _Harvey P. Dale_, Jul 01 2017 *)
%o (PARI) is(n) = {my(e = factor(n)[, 2], emax); if(n == 1, 0, emax = vecmax(e); emax > 1 && !(n % emax));} \\ _Amiram Eldar_, Jan 05 2024
%Y Intersection of A013929 and A336064.
%Y Cf. A059956, A137257, A336065.
%K nonn
%O 1,1
%A _Giovanni Teofilatto_, Sep 28 2008
%E Adapted definition, inserted 18, 20 and extended. - _R. J. Mathar_, Oct 24 2008
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