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%I #18 Jan 14 2013 10:25:32
%S 5,10,13,15,17,19,20,23,25,26,30,31,34,35,37,38,39,40,41,43,45,46,50,
%T 51,52,53,55,57,59,60,61,62,65,67,68,69,70,71,73,74,75,78,79,80,82,83,
%U 85,86,89,90,91,92,93,95,97,100,101,102,103,104,105,106,107,109
%N Numbers not expressible as a product of Lucas numbers.
%C a(n+1) - a(n) <= 5 for all n.
%H Arkadiusz Wesolowski, <a href="/A200995/b200995.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LucasNumber.html">Lucas Number</a>
%H <a href="/index/Lu#Lucas">Index entries for Lucas sequences</a>
%e 65 = 5*13 is not the product of Lucas numbers, so 65 is in the sequence.
%t listMultiply[lst_] := Take[Union@Flatten@Table[lst[[i]]*lst[[j]], {i, Length[lst]}, {j, i}], 46]; A200381 = Nest[listMultiply, LucasL@Range[0, 9], 3]; Complement[Range@Last[A200381], A200381]
%Y Cf. A000032. Complement of A200381.
%K nonn
%O 1,1
%A _Arkadiusz Wesolowski_, Jan 07 2013
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