MathDB

Let

p

be a prime number and

a_1, \ldots, a_{p-1}

be not necessarily distinct nonzero elements of the

p

-element

\mathbb Z_p \pmod{p}

group. Prove that each element of

\mathbb Z_p

equals a sum of some of the

a_i

's (the empty sum is

0

).
(translated by Miklós Maróti)

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