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%I #18 Feb 16 2024 10:07:10
%S 240,336,528,560,624,810,816,880,912,1040,1104,1134,1232,1360,1392,
%T 1456,1488,1520,1776,1782,1840,1904,1968,2064,2106,2128,2256,2288,
%U 2320,2480,2544,2576,2754,2832,2835,2928,2960,2992,3078,3216,3248,3280,3344,3408
%N Product of the 4th power of a prime and 2 different distinct primes (p^4*q*r).
%H T. D. Noe, <a href="/A179644/b179644.txt">Table of n, a(n) for n = 1..1000</a>
%H <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 240=2^4*3*5,336=2^4*3*7,..810=2^3^4*5,..
%t f[n_]:=Sort[Last/@FactorInteger[n]]=={1,1,4}; Select[Range[4000], f]
%t Take[Union[#[[1]]^4 #[[2]]#[[3]]&/@(Flatten[Permutations/@ Subsets[ Prime[ Range[ 20]],{3}],1])],50] (* _Harvey P. Dale_, Feb 07 2013 *)
%o (PARI) list(lim)=my(v=List(),t);forprime(p=2,(lim\6)^(1/4),forprime(q=2,sqrt(lim\p^4),if(p==q,next);t=p^4*q;forprime(r=q+1,lim\t,if(p==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, A179643.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Jul 21 2010