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%I #14 Jul 24 2015 23:16:02
%S 18,50,75,98,147,242,245,338,363,507,578,605,722,845,847,867,1058,
%T 1083,1183,1445,1587,1682,1805,1859,1922,2023,2523,2527,2645,2738,
%U 2883,3179,3362,3698,3703,3757,3971,4107,4205,4418,4693,4805,5043,5547,5618,5819
%N Numbers with ordered prime signature (1,2).
%C Numbers of the form p*q^2 where p and q are primes with p < q.
%C A054753 contains natural numbers with ordered prime signatures (2,1) and (1,2).
%H Enrique Pérez Herrero, <a href="/A095990/b095990.txt">Table of n, a(n) for n = 1..3000</a>
%H OEIS Wiki, <a href="http://oeis.org/wiki/Ordered_prime_signatures">Ordered prime signatures</a>
%e 18 = 2*3*3, 50 = 2*5*5, 75 = 3*5*5, 98 = 2*7*7, 147 = 3*7*7, ...
%t Take[ Sort[ Flatten[ Table[ Prime[p]*Prime[q]^2, {q, 2, 16}, {p, q - 1}]]], 46] (* _Robert G. Wilson v_, Jul 23 2004 *)
%o (PARI) list(lim)=my(v=List());forprime(q=3, sqrtint(lim\2), forprime(p=2, min(lim\q^2,q-1), listput(v,p*q^2))); Set(v) \\ _Charles R Greathouse IV_, Feb 26 2014
%Y Subsequence of A071365.
%Y Cf. A054753, A095904, A096156.
%K easy,nonn
%O 1,1
%A _Alford Arnold_, Jul 18 2004
%E Edited and extended by _Robert G. Wilson v_, Jul 23 2004
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