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%I #2 Mar 31 2012 19:53:46
%S 12,84,494,3696,30574
%N Number of circular permutations of length n with no consecutive triples i,i+2,i+4 (mod n) or i,i-2,i-4 (mod n).
%C Circular permutations are permutations whose indices are from the ring of integers modulo n.
%e For n=5 there are (5-1)!-a(5)=12 circular permutations with triples i,i+2,i+4 (mod 5) or triples i,i-2,i-4 (mod 5). An example of one is (0,3,1,2,4) because of the progression 0,3,1 (mod 5).
%Y Cf. A078628, A174076, A174077, A174078.
%K nonn
%O 5,1
%A _Isaac Lambert_, Mar 10 2010
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