How to play

  • The variables represents unique integers ranging from 1 to the number of variables;
  • Multiplication is implicit: AB means A times B, or A * B;
  • Based on the clues (equations and inequations), use the grid to create relations between variables and values:
    • Click once on a square to mark that value as false;
    • Click twice to assign the chosen value to the variable;
    • Click three times to clear the square.
  • The color of a clue changes after you assign values to all of its variables:
    • GREEN means that the statement is true;
    • RED means that the statement is false.
  • Click on a clue to mark it as used;
  • The game ends when all values are correctly assigned to the variables.


  • Figuring out which variables can't have the lowest or the highest values is a good starting point, e.g, A > B shows that A ≠ 1;
  • Analyzing the hypothetical equation C + D = 4, we can make the following statements:
  • Another quick tip: A = 2B means that A is even;
  • Don't be afraid of using pen and paper. Some puzzles might require it.

More 7x7 puzzles

  • A = B + E + G
  • EG + F = B + C
  • C = B + F
  • A = AG


  • DE = 3C + E + F
  • B + D = C + 8
  • CE + F = A


  • G ≥ 2
  • D + F = 6
  • C + EF + E + F = AE + AG + BG + G
  • A + D ≥ C
  • G < 4


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