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Squarefree composite k such that the smallest nondivisor prime is less than the greatest prime factor, i.e., A053669(k) < A006530(k).
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%I #26 Jan 07 2024 14:19:20

%S 10,14,15,21,22,26,33,34,35,38,39,42,46,51,55,57,58,62,65,66,69,70,74,

%T 77,78,82,85,86,87,91,93,94,95,102,105,106,110,111,114,115,118,119,

%U 122,123,129,130,133,134,138,141,142,143,145,146,154,155,158,159,161

%N Squarefree composite k such that the smallest nondivisor prime is less than the greatest prime factor, i.e., A053669(k) < A006530(k).

%C Squarefree numbers without the empty product, primes, and primorials.

%H Michael De Vlieger, <a href="/A366413/b366413.txt">Table of n, a(n) for n = 1..10000</a>

%F {a(n)} = { k : Omega(k) = omega(k) > 2, A053669(k) < A006530(k) }.

%F {a(n)} = { A120944 \ A002110 }.

%t s = Select[Range[6, 2^10], And[SquareFreeQ[#], CompositeQ[#] ] &]; Complement[s, Most@ FoldWhileList[Times, 6, Prime@ Range[3, 120], # <= s[[-1]] &] ]

%Y Cf. A000040, A001221, A001222, A002110, A005117, A006530, A053669, A120944.

%K nonn,easy

%O 1,1

%A _Michael De Vlieger_, Jan 07 2024