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Richard Walker

Spooky Primes

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Edited by Richard Walker, Sunday, 1 Nov 2020, 13:40

Think of any number whatsoever and there is a prime number starting with the digits of that number. For example if you pick 42, 421 is prime. In fact there are infinitely many primes beginning with 42, such as 421 or 42139 ...

Another example: the first primes starting with the current year number and the next are 20201 and 20219.

In every case, for any sequence of non-zero digits, infinitely many prime numbers start with that sequence. For instance infinitely many primes begin with 3142592. I guess I could find the first, in fact I will try in the morning.

And in fact I found three!

314159207 314159227 314159257


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