Mathrax consists of a square grid. The goal is to fill in each cell with numbers from 1 to N, where N is the size of the puzzle's side. No number may appear twice in any row or column. Circles with additional conditions may be situated on intersections of lines inside the grid; a circle may contain:* A number and a sign of mathematical operation (addition, subtraction, multiplication, division) - a number is a result of an operation execution with numbers in diagonally adjacent cells. * A letter "E" ("even") - all numbers in four cells are even. * A letter "O" ("odd") - all numbers in four cells are odd.============KEYWORDS/TAGS: logic games - logic game puzzle - logic puzzles - logic puzzle books for adults - logic puzzle books for teens - logic puzzle for adults - logic puzzles riddles - brainteasers for adults - brainteaser puzzles for adults - brainteaser books for adults - brainteaser adults - brainteaser for adults - brainteaser games for adults - brainteaser jigsaw puzzles - logic puzzle large print
