Half the number of n X n binary matrices, symmetric under vertical reflection, having equal row sums.
A140954
Half the number of n X n binary matrices, symmetric under vertical reflection, having equal row sums.
Terms
- a(0) =1a(1) =2a(2) =10a(3) =35a(4) =1126a(5) =7592a(6) =1697508a(7) =22458249a(8) =36000614026a(9) =941605438142
External references
- oeis: A140954