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%I #7 May 07 2015 10:07:51
%S 4,9,15,21,33,38,58,65,86,106,121,129,265,511,2038,2059,4097,4174,
%T 7894,16021,19857,31313,32419,33238,37711,116197,196609,220937,262978,
%U 273926,955743,34826059,64229819,67835071,77834009,497049562,4370946037
%N Semiprimes in A103376.
%C Intersection of A103376 with A001358.
%t SemiprimeQ[n_] := Plus @@ FactorInteger[n][[All, 2]] == 2; k = 8; Do[a[n] = 1, {n, k + 1}]; a[n_] := a[n] = a[n - k] + a[n - k - 1]; Union[Select[Array[a, 280], SemiprimeQ]]
%t Union[Select[LinearRecurrence[{0,0,0,0,0,0,0,1,1},{1,1,1,1,1,1,1,1,1},300],PrimeOmega[#]==2&]] (* _Harvey P. Dale_, May 07 2015 *)
%Y Cf. A001358, A103376, A103386, A103392-A103401.
%K nonn,easy
%O 1,1
%A _Jonathan Vos Post_, Feb 05 2005
%E Edited and extended by _Ray Chandler_, Feb 10 2005