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Informally:

Take any positive whole number. Can you create a prime number by adding digits to the end of the number?

Formally: Let N be the positive whole number written d1d2d3...dm.

di being 0 to 9, d1 not equal to 0. Is there a prime number that has d1d2d3...dm for its first m digits?

Not use to writing math on a keyboard.

Has this question ever been investigated? Is it trivial?

Thank you in advance for your time , knowledge and effort.

Hello Emil

I've never seen this before. But I'm pretty sure there are an infinity of prime numbers that start with those m digits. There must be a short proof, but I can't think of one immediately.

I'll get back to you if I come up with one.

best wishes

vijilant

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