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%I #16 Mar 13 2022 19:31:37
%S 0,1,2,3,5,9,15,28,50,93,169,321,591,1118,2098,3973,7501,14273,27103,
%T 51722,98710,188935,361937,694911,1335471,2570966,4954794,9562165,
%U 18473141,35730493,69176559,134067508,260062338,504918961,981117305,1907954345
%N Number of binary necklaces with n beads and at least two consecutive black beads.
%H Marko R. Riedel et al., <a href="https://math.stackexchange.com/questions/4376420/">Necklaces made of black and white beads</a>, Math StackExchange, Feb 2022.
%H Marko Riedel, <a href="/A351359/a351359.maple.txt">Maple code for sequence from cited link.</a>
%F a(n) = A000031(n) - A000358(n).
%Y Cf. A351356, A351357, A351358, A351360, A351361.
%K nonn
%O 1,3
%A _Marko Riedel_, Feb 08 2022