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Relatively Prime

Posted: April 1, 2024

54 % of users got this correct

It is well known that since 7 and 11 are relatively prime, there is a positive integer, F, where any integer greater than F can be written as a nonnegative linear combination of 7 and 11. Find the number of positive integers which cannot be written as a nonnegative linear combination of 7 and 11 (7x + 11y where both x and y are nonnegative integers).

Problem submitted by Pat Costello, Eastern Kentucky University

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