MathCastle
Proof Writing & Problem SolvingSuperchallenge

Proof Writing & Problem Solving · Superchallenge problem

For how many nn with 1≤n≤1001 \le n \le 100 does there EXIST an ordering a1,a2,…,ana_1, a_2, \ldots, a_n of the numbers 1,2,…,n1, 2, \ldots, n whose partial sums a1, a1+a2, …, a1+a2+⋯+ana_1,\ a_1 + a_2,\ \ldots,\ a_1 + a_2 + \cdots + a_n leave nn different remainders when divided by nn?

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