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).

A078673

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).

Terms

    a(0) =1a(1) =1a(2) =0a(3) =2a(4) =6a(5) =38a(6) =247a(7) =1831a(8) =15287a(9) =142199a(10) =1459462a(11) =16395802a(12) =200200031a(13) =2640841839a(14) =37433428955a(15) =567531704959

External references