What is the Post-office Problem for n>2?

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Hi, All:

I was hoping someone would know a source for the Post-office, say POP problem, n>2.

For n=2, POP asks, given a pair of positive integers p, q, with (p,q)=1, to find the largest

positive integer M that cannot be written as a nonnegative combination of p,q (so, if p,q

are resp. the values of stamps, M is the largest-priced of a package that cannot be

paid-for with p-stamps and q-stamps. ). For n=2, this number is (p-1)(q-1)-1 .

Proof is not too hard.

Anyway, for n>2 we have an n-ple (x1 x2,...,xn)

of relatively-prime positive integers , and we want to find M . I don't even know the

results for n=3 . Any sources, refs? Thanks in Advance.


Anyway, for n=3, we have a tri
 
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Nice.Thanks for the link.
 

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