Number of ways of placing kings with no more than 4 mutual attacks on an n X n chessboard symmetric about main diagonal.
A143889
Number of ways of placing kings with no more than 4 mutual attacks on an n X n chessboard symmetric about main diagonal.
Terms
- a(0) =1a(1) =2a(2) =7a(3) =33a(4) =202a(5) =1671a(6) =17279a(7) =234724a(8) =4081665a(9) =92343898a(10) =2711730350a(11) =103991393887
External references
- oeis: A143889