Number of nXnXn 0..6 triangular arrays with each element x equal to the number of its neighbors equal to 2,1,1,0,0,0,0 for x=0,1,2,3,4,5,6.

A197721

Number of nXnXn 0..6 triangular arrays with each element x equal to the number of its neighbors equal to 2,1,1,0,0,0,0 for x=0,1,2,3,4,5,6.

Terms

    a(0) =1a(1) =7a(2) =25a(3) =409a(4) =14185a(5) =1029761a(6) =168151040a(7) =60063611063

External references