15978924

Appears in sequences

• Number of ways to reciprocally link elements of an n X n array either to themselves or to exactly two horizontal, vertical or antidiagonal neighbors.at n=4A220682
• Number of ways to reciprocally link elements of an nX5 array either to themselves or to exactly two horizontal, vertical or antidiagonal neighbors.at n=4A220685
• T(n,k)=Number of ways to reciprocally link elements of an nXk array either to themselves or to exactly two horizontal, vertical or antidiagonal neighbors.at n=40A220688