MathDB

2015 Guts #20

Source:

July 28, 2022

2015Guts Test

Problem Statement

The sequence

a_1,a_2,\dots,a_{13}

is a geometric sequence with

a_1=a

and common ratio

r

, where

a

and

r

are positive integers. Given that

\log_{2015}a_1+\log_{2015}a_2+\dots+\log_{2015}a_{13}=2015,

find the number of possible ordered pairs

(a,r)

.

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