Number of -1..1 arrays x(i) of n+1 elements i=1..n+1 with x(i)+x(j), x(i+1)+x(j+1), -(x(i)+x(j+1)), and -(x(i+1)+x(j)) having two, three or four distinct values for every i<=n and j<=n.

A211479

Number of -1..1 arrays x(i) of n+1 elements i=1..n+1 with x(i)+x(j), x(i+1)+x(j+1), -(x(i)+x(j+1)), and -(x(i+1)+x(j)) having two, three or four distinct values for every i<=n and j<=n.

Terms

    a(0) =8a(1) =22a(2) =58a(3) =150a(4) =382a(5) =962a(6) =2402a(7) =5958a(8) =14702a(9) =36130a(10) =88498a(11) =216198a(12) =527038a(13) =1282562a(14) =3116738a(15) =7565190a(16) =18345422a(17) =44452642a(18) =107643922a(19) =260526918a(20) =630270622a(21) =1524213890a(22) =3684989858a(23) =8906776518a(24) =21523708718a(25) =52004525602a(26) =125633423218

External references