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<h2>Prime digit replacements</h2>
<h3>Problem 51</h3>
<div style="font-size:80%;color:#999;">Published on 29 August 2003 at 06:00 pm [Server Time]</div>
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<!--<p>By replacing the 1<sup>st</sup> digit of *57, it turns out that six of the possible values: 157, 257, 457, 557, 757, and 857, are all prime.</p> -->
<p>By replacing the 1<sup>st</sup> digit of the 2-digit number *3, it turns out that six of the nine possible values: 13, 23, 43, 53, 73, and 83, are all prime.</p>
<p>By replacing the 3<sup>rd</sup> and 4<sup>th</sup> digits of 56**3 with the same digit, this 5-digit number is the first example having seven primes among the ten generated numbers, yielding the family: 56003, 56113, 56333, 56443, 56663, 56773, and 56993. Consequently 56003, being the first member of this family, is the smallest prime with this property.</p>
<p>Find the smallest prime which, by replacing part of the number (not necessarily adjacent digits) with the same digit, is part of an eight prime value family.</p>

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