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%I #21 Feb 13 2024 07:01:30
%S 180,252,300,396,450,468,588,612,684,700,828,882,980,1044,1100,1116,
%T 1300,1332,1452,1476,1548,1575,1692,1700,1900,1908,2028,2124,2156,
%U 2178,2196,2205,2300,2412,2420,2450,2475,2548,2556,2628,2844,2900,2925,2988
%N Products of exactly 2 distinct squares of primes and a different prime (p^2 * q^2 * r).
%C A050326(a(n)) = 5, subsequence of A225228. - _Reinhard Zumkeller_, May 03 2013
%H T. D. Noe, <a href="/A179643/b179643.txt">Table of n, a(n) for n = 1..1000</a>
%H Will Nicholes, <a href="http://willnicholes.com/math/primesiglist.htm">Prime Signatures</a>
%H <a href="/index/Pri#prime_signature">Index to sequences related to prime signature</a>
%e 180 = 2^2 * 3^2 * 5, 252 = 2^2 * 3^2 * 7, 300 = 2^2 * 3 * 5^2, ...
%t f[n_]:=Sort[Last/@FactorInteger[n]]=={1,2,2}; Select[Range[3000], f]
%o (PARI) list(lim)=my(v=List(),t);forprime(p=2,sqrt(lim\12),forprime(q=p+1,sqrt(lim\p^2\2),t=(p*q)^2;forprime(r=2,lim\t,if(p==r||q==r,next);listput(v,t*r))));vecsort(Vec(v)) \\ _Charles R Greathouse IV_, Jul 19 2011
%Y Cf. A006881, A007304, A065036, A085986, A085987, A178739, A179642.
%Y Cf. A179695.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Jul 21 2010
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