Half the number of symmetric n X n binary matrices having equal row sums.
A140988
Half the number of symmetric n X n binary matrices having equal row sums.
Terms
- a(0) =1a(1) =2a(2) =5a(3) =20a(4) =139a(5) =1777a(6) =42295a(7) =1888140a(8) =158903233a(9) =25355226287
External references
- oeis: A140988