Number of n X n symmetric binary matrices with each 1 adjacent to no more than 2 horizontally or vertically neighboring 1s.
A191507
Number of n X n symmetric binary matrices with each 1 adjacent to no more than 2 horizontally or vertically neighboring 1s.
Terms
- a(0) =2a(1) =8a(2) =52a(3) =646a(4) =14570a(5) =599702a(6) =45191945a(7) =6225542127
External references
- oeis: A191507