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Old 11-28-2000, 10:20 PM
Little Nemo Little Nemo is offline
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Join Date: Dec 1999
Location: Western New York
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The co-worker gave the definition of semi-prime as a number divisible by itself, 1, and one other number (for instance, 9....1X9 and 3X3).
Assuming that the true definition of semi-prime numbers is the first one, the only numbers available are odd, square numbers whose square root = a prime number. Seems like a small amount, huh? But another way to put it is: take any prime, multiply it by itself, and you get a semi-square number. Since there are an infinite number of primes, there must, logically, be an infinite number of semi-primes.
They're somewhat more common than this. The definition doesn't restrict itself only to the squares of prime numbers. Any number that could be expressed as P to the Nth power, where P is a prime number and N is any integer greater than one, is a semi-prime number (assuming that this definition is correct). So for every prime number there would be an infinite amount of corresponding semi-prime numbers.