Let n be an integer greater than 1, and let S for
_{i}i between 1 and n-1 be a permutation over the numbers 1 through
n-1. Define T as follows:
_{i}
S_{1}+...+S_{n-1}
mod n
For which values of T is also a permutation over the numbers 1
through _{i}n-1?
For which values of i,
S+_{i}S-_{n}i=n?
For credit, answer both questions with proof. |
## List of solvers:Hongcheng Zhu (1 May 13:45)Bojan Bašić (4 May 01:59) Mark Tilford (4 May 11:39) Dan Dima (7 May 05:25) Or Sheffet and Itsik Horovitz (19 May 00:12) |

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