Number of n X n symmetric binary matrices with all row sums 4.
A139670
Number of n X n symmetric binary matrices with all row sums 4.
Terms
- a(0) =1a(1) =26a(2) =820a(3) =35150a(4) =1944530a(5) =133948836a(6) =11234051976
External references
- oeis: A139670