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Position of the last requested element when the elements of the n-th composition (in standard order) are requested from a self-organizing list initialized to (1, 2, 3, ...), where a requested element at position i is moved to position floor((i+1)/2).
4

%I #4 Jul 28 2024 17:01:57

%S 1,2,1,3,2,2,1,4,1,1,1,3,2,2,1,5,1,3,1,3,2,2,1,4,1,1,1,3,2,2,1,6,1,3,

%T 1,2,1,3,1,4,3,1,1,3,2,2,1,5,1,3,1,3,2,2,1,4,1,1,1,3,2,2,1,7,1,2,1,4,

%U 1,3,1,4,2,2,1,2,1,3,1,5,3,1,2,3,2,2,1

%N Position of the last requested element when the elements of the n-th composition (in standard order) are requested from a self-organizing list initialized to (1, 2, 3, ...), where a requested element at position i is moved to position floor((i+1)/2).

%C See A374995 for details.

%F a(n) = A374995(n) - A374995(A025480(n-1)).

%F Sum_{j=1..m} a(n*2^j+2^(j-1)) = m*(m+1)/2 if m >= A333766(n). This is a consequence of the fact that the first m positions of the list are occupied by the elements 1, ..., m, as long as no element larger than m has been requested so far.

%Y Analogous sequences for other updating strategies: A374997, A374998, A374999.

%Y Cf. A025480, A066099 (compositions in standard order), A333766, A374995.

%K nonn

%O 1,2

%A _Pontus von Brömssen_, Jul 27 2024