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1979 USAMO Problems/Problem 1

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Problem

Determine all non-negative integral solutions (n_1,n_2,\dots , n_{14}) if any, apart from permutations, of the Diophantine Equation n_1^4+n_2^4+\cdots +n_{14}^4=1599

Solution

Alternate solutions are always welcome. If you have a different, elegant solution to this problem, please add it to this page.

Recall that n_i^4\equiv 0,1\bmod{16} for all integers n_i. Thus the sum we have is anything from 0-14 mod16. But 1599=15mod16, and thus there are no integral solutions to the given Diophantine equation.

See also

1979 USAMO (Problems)
Preceded by
First Question
1 2 3 4 5 Followed by
Problem 2
All USAMO Problems and Solutions
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