Number of n X n symmetric 0..6 arrays with each element equal to at least two horizontal or vertical neighbors and with new values 0..6 introduced in lower triangular row major order.
A193000
Number of n X n symmetric 0..6 arrays with each element equal to at least two horizontal or vertical neighbors and with new values 0..6 introduced in lower triangular row major order.
Terms
- a(0) =0a(1) =1a(2) =1a(3) =6a(4) =35a(5) =697a(6) =19477a(7) =1565794a(8) =210688406a(9) =77029067005
External references
- oeis: A193000