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Putnam
1955 Putnam
B5
B5
Part of
1955 Putnam
Problems
(1)
Putnam 1955 B5
Source:
5/24/2022
Given an infinite sequence of
0
0
0
's and
1
1
1
's and a fixed integer
k
,
k,
k
,
suppose that there are no more than
k
k
k
distinct blocks of
k
k
k
consecutive terms. Show that the sequence is eventually periodic. (For example, the sequence
11011010101
11011010101
11011010101
followed by alternating
0
0
0
's and
1
1
1
's indefinitely, which is periodic beginning with the fifth term.)
Putnam