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All-Russian Olympiad Regional Round
2004 All-Russian Olympiad Regional Round
10.6
10.6
Part of
2004 All-Russian Olympiad Regional Round
Problems
(1)
set of 5-digit numbers - All-Russian MO 2004 Regional (R4) 10.6
Source:
9/27/2024
A set of five-digit numbers
{
N
1
,
.
.
.
,
N
k
}
\{N_1, ...,N_k\}
{
N
1
,
...
,
N
k
}
is such that any five-digit number, all of whose digits are in non-decreasing order, coincides in at least one digit with at least one of the numbers
N
1
N_1
N
1
,
.
.
.
...
...
,
N
k
N_k
N
k
. Find the smallest possible value of
k
k
k
.
number theory
Digits