Number of x X n symmetric binary matrices containing no more than three 1s in any 2 X 2 sub-block.
A139008
Number of x X n symmetric binary matrices containing no more than three 1s in any 2 X 2 sub-block.
Terms
- a(0) =1a(1) =2a(2) =7a(3) =49a(4) =648a(5) =16475a(6) =801489a(7) =74700792a(8) =13333992705
External references
- oeis: A139008