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%I #14 Oct 15 2023 09:26:23
%S 0,0,1,1,0,2,1,0,3,0,4,2,4,0,5,4,1,2,2,3,3,2,1,4,1,3,4,4,3,3,4,4,5,5,
%T 4,6,5,7,6,1,1,6,0,6,0,7,1,1,8,7,6,7,7,1,4,4,3,10,9,2,0,8,10,4,5,5,8,
%U 0,9,5,4,2,6,2,6,1,6,12,5,7,5,11,12,12,6,7,7,5,1,9,8,1,3,2,13,0
%N a(0) = 0; for n > 0, a(n) is the number of terms prior to the term a(n-1-a(n-1)) that equal a(n-1-a(n-1)).
%C In the first 10 million terms the value 4 appears the most often, 11838 times, although the count of neighboring values is less than 2% different. It is unknown if this stays the most common term as n increases. In the same range on thirty-eight occasions there are three consecutive equal terms, the first time being a(105) = a(106) = a(107) = 8. It is unknown if four or more consecutive terms eventually appear.
%H Scott R. Shannon, <a href="/A366548/b366548.txt">Table of n, a(n) for n = 0..10000</a>
%H Scott R. Shannon, <a href="/A366548/a366548.png">Image of the first 10 million terms</a>.
%e a(2) = 1 as a(2-1-a(2-1)) = a(1-0) = a(1) = 0, and there is one term prior to a(1) that equals 0, namely a(0).
%e a(6) = 1 as a(6-1-a(6-1)) = a(5-2) = a(3) = 1, and there is one term prior to a(3) that equals 1, namely a(2).
%Y Cf. A366549, A363193, A354971, A181391, A342585.
%K nonn,look
%O 0,6
%A _Scott R. Shannon_, Oct 13 2023