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Doashl3599
07-06-2009, 04:47 PM
Here is the problem that has got me stumped.
Mathematicians have been searching for a formula that yields prime numbers. One such formula was x (squared)-x+41. Select some numbers for x, substitute them in the formula, and see if prime numbers occur. Try to find a number for x that when substituted in the formula yields a composite number.
I haven't got a clue of how to figure the formula.
Please help.
So lost
Dori

Subhotosh Khan
07-06-2009, 08:47 PM
Here is the problem that has got me stumped.
Mathematicians have been searching for a formula that yields prime numbers. One such formula was x (squared)-x+41. Select some numbers for x, substitute them in the formula, and see if prime numbers occur. Try to find a number for x that when substituted in the formula yields a composite number.
I haven't got a clue of how to figure the formula.
Please help.
So lost
Dori

Hint:

x2 - x + 41 = x(x-1) + 41

What happens when x is a factor of 41?
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http://www.mathgoodies.com/forums/topic ... C_ID=33900 (http://www.mathgoodies.com/forums/topic.asp?TOPIC_ID=33900)