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        riddles >> medium >> primes puzzle
        
(Message started by: amichail on Dec 1^st, 2006, 7:45pm)

Title: primes puzzle
Post by amichail on Dec 1^st, 2006, 7:45pm

Consider the following set:

S={2,3,5,7,11,19,41,61,89,409,449,499,881,991,6469,6949,9001,9049, 9649,9949,60649,666649,946669,60000049,66000049,66600049}

Prove that any prime is already a member of S or it can be transformed to at least one of these 26 primes in S, by the simple and only procedure of eliminating one or several digits.