Lua Random number generator always produces the same number - random

Question

I have looked up several tutorials on how to generate random numbers with lua, each said to use math.random(), so I did. however, every time I use it I get the same number every time, I have tried rewriting the code, and I always get the lowest possible number. I even included a random seed based on the OS time. code below.
require "math"
math.randomseed(os.time())
num = math.random(0,10)
print(num)

Answer 1

I'm using the random function like this:
math.randomseed(os.time())
num = math.random() and math.random() and math.random() and math.random(0, 10)
This is working fine. An other option would be to improve the built-in random function, described here.

Answer 2

This might help! I had to use these functions to write a class that generates Nano IDs. I basically used the milliseconds from the os.clock() function and used that for math.randomseed().
NanoId = {
validCharacters = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_-",
generate = function (size, validChars)
local response = ""
local ms = string.match(tostring(os.clock()), "%d%.(%d+)")
local temp = math.randomseed(ms)
if (size > 0 and string.len(validChars) > 0) then
for i = 1, size do
local num = math.random(string.len(validChars))
response = response..string.sub(validChars, num, num)
end
end
return response
end
}
function NanoId:Generate()
return self.generate(21, self.validCharacters)
end
-- Runtime Testing
for i = 1, 10 do
print(NanoId:Generate())
end
--[[
Output:
>>> p2r2-WqwvzvoIljKa6qDH
>>> pMoxTET2BrIjYUVXNMDNH
>>> w-nN7J0RVDdN6-R9iv4i-
>>> cfRMzXB4jZmc3quWEkAxj
>>> aFeYCA2kgOx-s4UN02s0s
>>> xegA--_EjEmcDk3Q1zh7K
>>> 6dkVRaNpW4cMwzCPDL3zt
>>> R2Fct5Up5OwnHeExDnqZI
>>> JwnlLZcp8kml-MHUEFAgm
>>> xPr5dULuv48UMaSTzdW5J
]]