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coloring a 2x5 table

Source: 2020 Dürer Math Competition Finals Day2 E12 https://artofproblemsolving.com/community/c1622639_2020_

January 7, 2022
combinatoricsColoring

Problem Statement

We have a white table with 22 rows and 55 columns , and would like to colour all cells of the table according to the following rules:
\bullet We must colour the cell in the bottom left corner first. \bullet After that, we can only colour a cell if some adjacent cell has already been coloured. (Two cells are adjacent if they share an edge.)
How many different orders are there for colouring all 1010 squares (following these rules)?