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2 is prime, but 12, 22, ..., 92 are not.

arithmetic/digits/prime/prefix.one

Problem

2 is prime, but 12, 22, ..., 92 are not.  Similarly, 5 is prime
whereas 15, 25, ..., 95 are not.  What is the next prime number
which is composite when any digit is prefixed?
Show solution
149