Write a function called prime_pairs that returns the smallest prime number p smaller than 100,000 such that (p + n) is also prime, where n is a scalar integer and is the sole input argument to the function. If no such number exists, then the function

function pr=prime(n)
    np=1;c=0;
  pr=zeros(1,n);
  while np<=n
      if isprime(np)
          c=c+1;
          pr(c)=np;
      end
      np=np+1;
  end
  pr=pr(1:c);

[Walter Roberson]

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