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Hello !

This is my first post on this list, after lots of reading.

So i'm learning Lua. I find it great so far.
I'm trying to write code "thinking in Lua" not just "thinking in C, then translating to Lua".

So i'm going through Project Euler' problems. I recently solved this one :

Using this code :

function mesure(n)
  local i = 0
  while n ~= 1 do
    if n % 2 == 0 then n = n / 2
    else n = 3*n + 1 end
    i = i + 1
  return i

local begin = os.time()

local max = 0
local maxi = 0
for i = 1, arg[1] or 10 do
  local new = mesure(i)
  if new > max then
    max = new
    maxi = i

io.write("Done. ", os.difftime(os.time(), begin), "s.\n")
io.write("i = ", maxi)

Also on pastebin here :

When running it until 1,000,000 it finishes in about 15 seconds. (I have a 1.83Ghz processor).
I'm not really concerned about performance, and i'm sure there's a better algorithm for solving this problem. But an equivalent algorithm in C finishes about 6 times faster. 
Is this what one should expect from Lua ?

I'm also concerned about the style of my code. Is this making a good use of Lua ?
I don't get the reflex of using the beautiful things it provides yet, like the generic for, multiple assignments, function as prime values, etc.

How do you do that ? :D