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%I #13 Jul 10 2013 20:40:28
%S 48,320,486,3072,3150,6174,7128,7650,10890,11466,15000,18018,18810,
%T 25578,27846,29400,30240,39546,40590,45056,45927,53010,54600,55062,
%U 59202,73440,75582,77418,80910,85800,90552,92106,95238,96642,98838
%N Composite numbers such that the square root of the sum of squares of their prime factors is a prime.
%C Numbers included in A134605, but not in A134606. a(1)=48 is the minimal number with this property.
%H Hieronymus Fischer, <a href="/A134607/b134607.txt">Table of n, a(n) for n = 1..1000</a>
%e a(2)=320, since 320=2*2*2*2*2*2*5 and sqrt(6*2^2+5^2)=sqrt(49)=7.
%t sspfpQ[n_]:=PrimeQ[Sqrt[Total[Flatten[Table[#[[1]],{#[[2]]}]&/@ FactorInteger[ n]]^2]]]; upto=100000;With[{comps=Complement[ Range[ upto],Prime[ Range[PrimePi[upto]]]]},Select[comps,sspfpQ]] (* _Harvey P. Dale_, Jul 10 2013 *)
%Y Cf. A001597, A025475, A134333, A134344, A134376.
%Y Cf. A134600, A134602, A134605, A134611, A134616, A134618, A134620.
%K nonn
%O 1,1
%A _Hieronymus Fischer_, Nov 11 2007
%E Minor edits by _Hieronymus Fischer_, Apr 19 2013