Number of arrays of n+2 integers in -2..2 with sum zero and adjacent elements differing in absolute value.

A202956

Number of arrays of n+2 integers in -2..2 with sum zero and adjacent elements differing in absolute value.

Terms

    a(0) =6a(1) =28a(2) =82a(3) =200a(4) =524a(5) =1724a(6) =5908a(7) =18340a(8) =53680a(9) =162080a(10) =515626a(11) =1651124a(12) =5168256a(13) =15997588a(14) =50018962a(15) =158377344a(16) =502147864a(17) =1584312736a(18) =4991421852a(19) =15779264936a(20) =50053153920a(21) =158866891408a(22) =503893624892

External references