def large_enough_prime(input)
      standard_primes.each do |prime|
        return prime if prime > input
      end
      fail CannotFindLargeEnoughPrime, "Input too large"
    end
def large_enough_prime(input)
      standard_primes.each do |prime|
        return prime if prime > input
      end
      fail CannotFindLargeEnoughPrime, "Input too large"
    end
Retrieves the next largest prime for the largest number in batch

 Example

   Prime.large_enough_prime 4
   # => 7

 @param input [Integer] the integer to find the next largest prime for
 @return [Integer] the next largest prime
 @raise [CannotFindLargeEnoughPrime] raised when input is too large and
   no large enough prime can be found