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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A372008 Maximum number of moves to solve "Reverse The List of Integers" game with high value n.

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%I A372008 #29 Apr 16 2024 07:08:15
%S A372008 0,0,0,0,0,14,26,74,86,126,106,130
%N A372008 Maximum number of moves to solve "Reverse The List of Integers" game with high value n.
%C A372008 Given a list of unique positive integers with a maximum value n, you can perform the following "moves": a) split one number into two numbers that sum to the original number, or b) add two adjacent numbers into a new number.  In all moves the list must not have duplicates or contain a value greater than n.
%C A372008 Some lists can be reversed (e.g., 1,6,3) and some cannot (e.g., 1,6,4).  The "distance" of a list is the smallest number of a moves to reverse it; this sequence deals with the maximum distance of all reversible lists.
%C A372008 For n<6, the only lists that can be reversed are the ones that are single-number sequences that are implicitly reversed in 0 moves.
%H A372008 Alexandre Muñiz, <a href="https://mathstodon.xyz/@two_star/112242224494626411">Reverse The List of Integers</a>, Discussion on Mastodon.
%H A372008 Alexandre Muñiz, <a href="https://news.ycombinator.com/item?id=40010066">Reverse The List of Integers</a>, Discussion on Hacker News.
%e A372008 For n=6, the worst case is 1,6,3 -> 1,4,2,3 -> 5,2,3 -> 4,1,2,3 -> 4,1,5 -> 4,6 -> 1,3,6 -> 1,3,2,4 -> 1,5,4 -> 6,4 -> 5,1,4 -> 3,2,1,4 -> 3,2,5 -> 3,2,4,1 -> 3,6,1.  There is no shorter solution for this list, and no other reversible list requires more than 14 moves. So a(6) = 14.
%K A372008 nonn,more
%O A372008 1,6
%A A372008 _Tomas Rokicki_, Apr 15 2024