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%I #7 Mar 30 2012 18:40:27
%S 4,9,15,21,33,38,58,65,86,106,121,129,265,2049,3865,4163,8557,14005,
%T 80413,104757,116333,152713,241354,2273893,2492909,16432401,31701485,
%U 34090613,263504954,424792297,1534443805,3233454667,10580401481
%N Semiprimes in A103375.
%C Intersection of A103375 with A001358.
%e 14005 is an element of this sequence because A103375(106) = 14005 and
%e 14005 is semiprime because 14005 = 5 * 2801 where both 5 and 2801 are primes. It is coincidence here that 106 = 2 * 53 is also semiprime.
%t SemiprimeQ[n_] := Plus @@ FactorInteger[n][[All, 2]] == 2; k = 7; Do[a[n] = 1, {n, k + 1}]; a[n_] := a[n] = a[n - k] + a[n - k - 1]; Union[Select[Array[a, 255], SemiprimeQ]]
%Y Cf. A001358, A103375, A103385, A103392-A103401.
%K nonn,easy
%O 1,1
%A _Jonathan Vos Post_, Feb 03 2005
%E Edited, corrected and extended by _Ray Chandler_ and _Robert G. Wilson v_, Feb 06 2005
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