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.

Tips

  • 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.

Logic Equations by size

4x4 »

  • C = D + 2
  • A = D + 1
  • A = B + 2

Solve

  • 4A = 3B
  • 2B = 4D

Solve

  • if A + D ≤ 6 then B < 1
  • if C ≤ 2 then A + B ≤ 4

Solve

5x5 »

  • B + C = A + 4
  • B + D = A + 1

Solve

  • C + E = A + B
  • C + D = B + E
  • E ≠ 2
  • A ≠ 5
  • E ≠ 4

Solve

  • D + E = B
  • B + D = A
  • A + E ≤ 6
  • C + E = A

Solve

6x6 »

  • 4A = 3D
  • 4B = 2D
  • D = 4C
  • E > F

Solve

  • D + E = C + F
  • B ≠ 2
  • D ≠ 6
  • B ≠ 1
  • B + C = A + F
  • D ≠ 4
  • B ≠ 5

Solve

  • A + F = E
  • B + C = F
  • C + D = E
  • C + F = D

Solve

7x7 »

  • A + F = 10
  • B + G = 10
  • B + C = 7
  • B + F = 9
  • A + C + E = 10

Solve

  • CD = B
  • C + F = B + G
  • F > B
  • C + F + G = E + 9

Solve

  • C = DF
  • F = G + 2
  • B + D = A + G

Solve

8x8 »

  • 2F = C
  • A > C
  • H = 2E
  • 2G = B
  • B > F
  • 3F = G
  • D > B

Solve

  • 4A = 3D
  • 4D = 2H
  • C > A
  • 3H = 4B
  • F > G
  • H = 4E
  • C > B

Solve

  • D + 9 = A + G
  • C = BE
  • A ≠ 8
  • A = E + 2F + 1
  • B + G = A

Solve

9x9 »

  • A + I = 5
  • F + H = 7
  • E + F = 6
  • G + I = 6
  • B + I = 9
  • A + D + F = 13

Solve

  • 4A = 3G
  • 4D = 2H
  • C > A
  • H = 4F
  • 3I = B

Solve

  • 2F = G
  • 2B = 3C
  • 4G = 2A
  • H = 3D
  • I ≠ 7

Solve

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