MathDB

max n, there is a_1a_2a_3...a_n divisible by a_2a_3...a_n}

Source: Czech-Polish-Slovak Junior Match 2017, individual p1 CPSJ

February 20, 2020

number theorydivisibleDigitsmax

Problem Statement

Find the largest integer

n \ge 3

for which there is a

n

-digit number

\overline{a_1a_2a_3...a_n}

with non-zero digits

a_1, a_2

and

a_n

, which is divisible by

\overline{a_2a_3...a_n}