this is quite a classic problem i think but im having difficulty finishing it off. If we have two stamps of positive values a and b, (greater than 1), what values can be expressed as a linear combination of these 2 stamps. If the stamps have a highest common factor greater than 1, then there are infinitely many 'bad' numbers. But if the numbers are coprime, after a certain point, all numbers are possible. For instance, with 5 and 8, in the list of possible numbers, you eventually get 28,29,30,31,32, therefore by adding 5's every other number is possible.(adsbygoogle = window.adsbygoogle || []).push({});

Can anyone help me prove the fact the if you have a and b, with a<b, then eventually you get 'a' consecutive numbers in the list of possibles. (therefore making all subsequent numbers possible).

Any other angle welcome!

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# Stamp problem

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