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%
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% Involution:
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\rput(2,3.5){$\longleftrightarrow$}
% LEFT PICTURE
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% The labeled grid
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% The minimal point of intersection:
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% The lattice paths
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% Starting points
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% Starting points
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% Ending points
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% RIGHT PICTURE
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% The labeled grid
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% The minimal point of intersection:
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% The lattice paths
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% Starting points
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% Starting points
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\pscircle[linecolor=white](-9,0.35){0.3}\rput(-9,0.35){${\scriptstyle\mathbf 3}$}
% Ending points
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