MathDB

2022 PUMaC Team #15

Source:

September 9, 2023

combinatorics

Problem Statement

Subsets

S

of the first 3

5

positive integers

\{1, 2, 3, ..., 35\}

are called contrived if

S

has size

4

and the sum of the squares of the elements of

S

is divisible by

7

. Find the number of contrived sets.

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