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%I #5 May 26 2019 15:00:32
%S 7,5,3,2,1,3,3,5,5
%N Minimal number of moves after which a group of stones of one color with exactly n liberties is possible on an infinite board in Go.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Go_(game)">Go (game)</a>
%e For n = 0: A white stone with 4 black stones adjacent to it has 0 liberties, which is possible after 7 moves, so a(0) = 7.
%e For n = 1: A white stone with 3 black stones adjacent to it has 1 liberty, which is possible after 5 moves (3 of black and 2 of white), so a(1) = 5.
%e For n = 2: A white stone with 2 black stones adjacent to it has 2 liberties, which is possible after 3 moves, so a(2) = 3.
%e For n = 3: A black stone with a single white stone adjacent to it has 3 liberties, which is possible after 2 moves, so a(3) = 2.
%e For n = 4: A single stone has 4 liberties, with that configuration possible after 1 move of black, so a(4) = 1.
%e For n = 5: A group of 2 black stones adjacent to a single white stone has 5 liberties, which is possible after 3 moves, so a(5) = 3.
%e For n = 6: A group of 2 black stones has 6 liberties, which is possible after 3 moves, so a(6) = 3.
%e For n = 7: A group of 3 black stones in a straight line with a single adjacent white stone or a group of 3 black stones in an L-shape have 7 liberties, both of which are possible after 5 moves, so a(7) = 5.
%e For n = 8: A group of 3 black stones in a straight line has 8 liberties, which is possible after 5 moves, so a(8) = 5.
%Y Cf. A089071, A275346, A320666.
%K nonn,more
%O 0,1
%A _Felix Fröhlich_, May 25 2019
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