MathDB
Putnam 2017 B6

Source:

December 3, 2017
PutnamPutnam 2017

Problem Statement

Find the number of ordered 6464-tuples {x0,x1,,x63}\{x_0,x_1,\dots,x_{63}\} such that x0,x1,,x63x_0,x_1,\dots,x_{63} are distinct elements of {1,2,,2017}\{1,2,\dots,2017\} and x0+x1+2x2+3x3++63x63x_0+x_1+2x_2+3x_3+\cdots+63x_{63} is divisible by 2017.2017.