Number of n X n symmetric binary matrices with each 1 adjacent to no more than 1 E, SE or S neighboring 1.

A191691

Number of n X n symmetric binary matrices with each 1 adjacent to no more than 1 E, SE or S neighboring 1.

Terms

    a(0) =2a(1) =6a(2) =32a(3) =294a(4) =4640a(5) =125338a(6) =5802288a(7) =459958324a(8) =62453890000

External references