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Number of ways of arranging the numbers 1..n in a circle so that there is no consecutive triple i, i+1, i+2 or i, i-1, i-2 (mod n).
8

%I #5 Mar 30 2012 16:49:37

%S 1,1,0,2,6,38,247,1831,15287,142199

%N Number of ways of arranging the numbers 1..n in a circle so that there is no consecutive triple i, i+1, i+2 or i, i-1, i-2 (mod n).

%C Arrangement that differ only in the direction in which the cycle is traversed do not count as different.

%H <a href="/index/La#lacings">Index entries for sequences related to shoe lacings</a>

%Y Apart from initial terms, A078628/2.

%K nonn

%O 1,4

%A _N. J. A. Sloane_, Dec 16 2002