# A number theory problem by Akshat Sharda

For a positive integer $$p$$ define a positive integer $$n$$ to be $$n-\text{safe}$$ if $$n$$ differs in absolute value by more than $$2$$ from all multiples of $$p$$. For example, the set of $$10-\text{safe}$$ numbers is $$3,4,5,6,7,13,14,\ldots$$

Find the number of positive integers $$≤10000$$ which are simultaneously $$7-\text{safe}, 11-\text{safe}$$ and $$13-\text{safe}$$.

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