Math-chess and the method of playing it

Claim 1

A math-chess for two players, comprising: a square checkerboard having sixty-four squares arranged in eight rows and eight columns thereon; thirty-two pieces divided into two distinguishable sets, each set having a color distinguishable from the color of the other set, each set having sixteen pieces said pieces of either color including respectively ten pieces of numeral: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, four pieces of mathematical symbol: +, -, *, ÷, and two pieces of unknown number.

Claim 7

A method for playing a math-chess which is composed of a square checkerboard having sixty-four squares arranged in eight rows and eight columns thereon and thirty-two pieces divided into two distinguishable sets, each set having a color distinguishable from the color of the other set, each set having sixteen pieces including ten pieces of numeral, four pieces of mathematical symbol and two pieces of unknown number comprising: (a) each player secretly disposing his own sixteen pieces in the squares of the two rows at the near end of the checherboard; (b) each player disclosing his own position to the other; (c) each player moving in turn to form an algebraic expression with his own pieces including at least one piece of mathematical symbol without any empty square between any two pieces of the expression which constitutes an equation with any of the opponent's piece or pieces on the checkerboard; (d) removing the opponent's piece or pieces on the checkerboard which constitutes the equation; (e) crying out what number the piece of unknown number representing in case a piece of unknown number is used in said expression; (f) restricting movement of one piece to any one of the eight squares neighbouring its own square or to other square by leaps without a limit to the number of squares over which it leaps on condition that these neighboring squares are occupied by pieces and that these squares are all in the same row or column with its own square or in the diagonal along the extension line of one of the two diagonals of its own square; (g) repeating steps (c), (d), (e) and (f) until all pieces of one player are taken or no piece is taken during a fixed number of turns.

Claim 8

A method for playing a math-chess which is composed of a square checkerboard having sixty-four squares arranged in eight rows and eight columns thereon and thirty-two pieces divided into two distinguishable sets, each set having a color distinguishable from the color of the other set, each set having sixteen pieces including ten pieces of numeral, four pieces of mathematical symbol and two pieces of unknown number comprising: (a) each player secretly disposing his own sixteen pieces in the squares of the two rows at the near end of the checherboard; (b) each player disclosing his own position to the other; (c) each player moving in turn to form an algebraic expression with his own pieces including at least one piece of mathematical symbol without any empty square between any two pieces of the expression which constitutes an equation with any of the opponent's piece or pieces on the checkerboard; (d) removing the opponent's piece or pieces on the checkerboard which constitutes the equation; (e) crying out what number the piece of unknown number representing in case a piece of unknown number is used in said expression; (f) restricting movement of one piece to any one of the eight squares neighbouring its own square or to other square by leaps without a limit to the number of squares over which it leaps on condition that these neighboring squares are occupied by pieces and that these squares are all in the same row or column with its own square or in the diagonal along the extension line of one of the two diagonals of its own square; (g) repeating steps (c), (d), (e) and (f) until all pieces of one player are taken or no piece is taken during a fixed number of turns.