Suppose a new fairy chess piece named the Wazir is introduced to chess. Wazirs can move from a position (x, y) to:
That is, they move orthogonally like the rook, but only one step at a time like the king. How many such wazirs can be placed on an N×N chessboard so that no two wazirs can attack each other?
On a 1×1 board, there can be only 1 such piece.
On a 2×2 board, there can be 2 such pieces.
On a 3×3 board, there can be 5 such pieces.
Given N, return the number of wazirs that can be placed on an N×N chessboard.
This is OEIS sequence A000982.
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