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There's a planet out in space called Zargon ........
On this planet these areĀ numbers that are called ziffles
These numbers are ziffles $56, 105, 28, 63, 49$
These numbers are not ziffles: $100, 18, 65, 9, 76$
Only two of these numbers are ziffles: $16, 14, 57, 24, 70$
So what is special about the ziffles?