Number of n X n symmetric 0..3 arrays with no element equal to the sum mod 4 of any two of its horizontal and vertical neighbors.
A193221
Number of n X n symmetric 0..3 arrays with no element equal to the sum mod 4 of any two of its horizontal and vertical neighbors.
Terms
- a(0) =4a(1) =27a(2) =201a(3) =2791a(4) =77245a(5) =4482957a(6) =547681823a(7) =138848752487
External references
- oeis: A193221