Number of ways of placing kings with no more than 4 mutual attacks on an n X n chessboard symmetric under horizontal and vertical reflection.
A143888
Number of ways of placing kings with no more than 4 mutual attacks on an n X n chessboard symmetric under horizontal and vertical reflection.
Terms
- a(0) =1a(1) =2a(2) =1a(3) =11a(4) =4a(5) =101a(6) =29a(7) =1592a(8) =263a(9) =43578a(10) =4424a(11) =1972239a(12) =117557a(13) =159790891a(14) =5394252a(15) =22035879309a(16) =430235439
External references
- oeis: A143888