Number of walks within N^2 (the first quadrant of Z^2) starting and ending at (0,0) and consisting of 2*n steps taken from {(-1, -1), (-1, 0), (-1, 1), (1, -1), (1, 0), (1, 1)}.

A151362

Number of walks within N^2 (the first quadrant of Z^2) starting and ending at (0,0) and consisting of 2*n steps taken from {(-1, -1), (-1, 0), (-1, 1), (1, -1), (1, 0), (1, 1)}.

Terms

    a(0) =1a(1) =2a(2) =18a(3) =255a(4) =4522a(5) =91896a(6) =2047452a(7) =48748986a(8) =1220457810a(9) =31779889284a(10) =854110511124

External references