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%I #9 Dec 23 2013 12:37:42
%S 1,1,3,5,12,21,33,81,177,338,667,1178,2031,4105,6872,20569,42744,
%T 84457,167863,315633,590081,1325032,2366125,4408350,8146016,16474904,
%U 30266484,67320433,112454976,230099960,417825921,1333610936,2714234540,5411487988,10800172911
%N Number of binary words of length n avoiding the subword given by the binary expansion of n.
%H Alois P. Heinz, <a href="/A234005/b234005.txt">Table of n, a(n) for n = 0..1000</a>
%e a(0) = 1: the empty word.
%e a(1) = 1: 0.
%e a(2) = 3: 00, 01, 11.
%e a(3) = 5: 000, 001, 010, 100, 101.
%e a(4) = 12: 0000, 0001, 0010, 0011, 0101, 0110, 0111, 1010, 1011, 1101, 1110, 1111.
%Y Main diagonal of A209972.
%Y Column k=0 of A233940.
%K nonn
%O 0,3
%A _Alois P. Heinz_, Dec 18 2013