MathDB

Each number from the set

\{1,2,3,4,5,6,7,8\}

is either colored red or blue, following these rules:
a) The number

4

is colored red, and there is at least one number colored blue. b) If two numbers

x, y

have different colors and

x + y \leq 8

, then the number

x + y

is colored blue. c) If two numbers

x, y

have different colors and

x \cdot y \leq 8

, then the number

x \cdot y

is colored red.
Find all possible ways the numbers from this set can be colored.

1