function validate1st8NotSame(value)
    if value:match("^(.)%1%1%1%1%1%1%1") then
      return false
    end
    return true
end
 
function validate1st8NoSame(value)
    if value:sub(1,8):match("(.).-%1") then
         return false
    end
    return true
end
 
print(validate1st8NotSame("aaaaaaaa")) --not valid
print(validate1st8NotSame("aaaaaaab")) --valid
print(validate1st8NotSame("aaaaaaa")) --!you should enforce 8+ charactesr otherwise this is valid
 
print(validate1st8NoSame("abcdefghe")) --valid
print(validate1st8NoSame("abcdefgae")) --invalid

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