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%I #24 Jan 12 2016 00:20:31
%S 183,249,361,371,413,459,487,501,515,525,609,613,639,697,749,763,795,
%T 823,893,911,931,1009,1043,1051,1081,1093,1213,1237,1263,1271,1275,
%U 1301,1373,1383,1393,1399,1425,1509,1513,1523,1543,1561,1581,1589,1617,1659,1663
%N Numbers n for which the numbers 6n+1, 3n+2, 6n+7 are all odd composite squarefree, but not all semiprimes.
%H Peter J. C. Moses, <a href="/A264779/b264779.txt">Table of n, a(n) for n = 1..2000</a>
%t semiPrimeQ:=Last[Total[FactorInteger[#]]]==2&;
%t A264779=Select[Range[1000],Map[Apply[And,#]&,Transpose[Map[{CompositeQ[#],OddQ[#],SquareFreeQ[#],semiPrimeQ[#]}&,{6#+1,3#+2,6#+7}]]]=={True,True,True,False}&]
%o (PARI) is(n)={bittest(n,0)&&Set(apply(issquarefree,n=[3*n+2,6*n+1,6*n+7]))==[1]&&vecmax(n=apply(omega,n))>2&&vecmin(n)>1} \\ _M. F. Hasler_, Nov 25 2015
%Y Cf. A001358, A263510, A264778.
%K nonn
%O 1,1
%A _Vladimir Shevelev_ and _Peter J. C. Moses_, Nov 24 2015
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