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Possible Duplicate:
Representing Any $n \geq 4$ as a Sum of 2’s and 5’s

Show that if you have enough three cent and four cent stamps then you can make any postage greater than six cents.

How would I prove this by induction?

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DaveHkl
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    See http://math.stackexchange.com/questions/102222/strong-mathematical-induction and http://math.stackexchange.com/questions/99712/representing-any-n-geq-4-as-a-sum-of-2s-and-5s and http://math.stackexchange.com/questions/145189/examples-of-mathematical-induction and http://math.stackexchange.com/questions/186356/non-trivial-induction-order – Gerry Myerson Nov 29 '12 at 00:58

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HINT: Show directly that you can make $6$ cents, $7$ cents, and $8$ cents. Then show that if you can make $n$ cents, you can make $n+3$ cents.

Brian M. Scott
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