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A325230 Numbers of the form p^k * q, p and q prime, p > q, k > 0.

%I A325230 #11 Apr 16 2019 17:30:47
%S A325230 6,10,14,15,18,21,22,26,33,34,35,38,39,46,50,51,54,55,57,58,62,65,69,
%T A325230 74,75,77,82,85,86,87,91,93,94,95,98,106,111,115,118,119,122,123,129,
%U A325230 133,134,141,142,143,145,146,147,155,158,159,161,162,166,177,178
%N A325230 Numbers of the form p^k * q, p and q prime, p > q, k > 0.
%H A325230 Robert Israel, <a href="/A325230/b325230.txt">Table of n, a(n) for n = 1..10000</a>
%e A325230 The sequence of terms together with their prime indices begins:
%e A325230     6: {1,2}
%e A325230    10: {1,3}
%e A325230    14: {1,4}
%e A325230    15: {2,3}
%e A325230    18: {1,2,2}
%e A325230    21: {2,4}
%e A325230    22: {1,5}
%e A325230    26: {1,6}
%e A325230    33: {2,5}
%e A325230    34: {1,7}
%e A325230    35: {3,4}
%e A325230    38: {1,8}
%e A325230    39: {2,6}
%e A325230    46: {1,9}
%e A325230    50: {1,3,3}
%e A325230    51: {2,7}
%e A325230    54: {1,2,2,2}
%e A325230    55: {3,5}
%e A325230    57: {2,8}
%e A325230    58: {1,10}
%p A325230 filter:= proc(n) local F;
%p A325230    F:= sort(ifactors(n)[2],(a,b)-> a[1]<b[1]);
%p A325230    nops(F) = 2 and F[1,2] = 1;
%p A325230 end proc:
%p A325230 select(filter, [$6..200]); # _Robert Israel_, Apr 14 2019
%t A325230 Select[Range[100],PrimeOmega[#/Power@@FactorInteger[#][[-1]]]==1&]
%o A325230 (Python)
%o A325230 from sympy import factorint
%o A325230 A325230_list = [n for n, m in ((n, factorint(n)) for n in range(2,10**6)) if len(m) == 2 and m[min(m)] == 1] # _Chai Wah Wu_, Apr 16 2019
%Y A325230 Positions of 1's in A325226.
%Y A325230 Cf. A056239, A093641, A112798, A174090, A257541, A307517, A325223, A325224, A325225, A325231.
%K A325230 nonn
%O A325230 1,1
%A A325230 _Gus Wiseman_, Apr 13 2019