il pot my soln neway... leave out the outer border of squares... each inner square has 4 neighbours wid common border... now 4 outer border: except the corner sq all have 3 sq wid common border...n the corners have 2 sq wid common border now each pair of sq are mapped together twice so devide by 2.. so v get [{36*4 +24*3+4*2}/2]/64C2=1/18
Moderation Team
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