43578

Appears in sequences

• 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.at n=9A143888
• Number of length-2n binary strings of the form xxyy, with x and y both nonempty.at n=11A347583
• Indices of consecutive prime-powers (exclusive) differing by 1. Positions of 1's in A057820.at n=12A375734