chance  = 70.21 -- I think that's 1.41 ?
basebet = 100
bethigh = true

After 1 loss -- increase by 150%
After 1 win -- Decrease by 50%

After 3 wins in a row -- reset to basebet
After 2 losses in a row -- Switch Under/Over
After 3 wins in a Row -- Switch Under/Over

I don't know how to get past the bethigh in the lua.

I think after some toiling around, I got it right:

chance=70.71
multiplier=0.50
multiplier2=2.5
base=.001
nextbet = base
bethigh = true


function dobet()

   if win then
      if (wins % 3 == 0) then
         nextbet = base
       bethigh = true
      else
        bethigh = false
         nextbet=previousbet*multiplier

      end
   else
      if (losses % 1 == 0) then
     nextbet = previousbet*multiplier2
     else
      if (currentstreak % -2 == 0) then
      bethigh = false
     else
     bethigh = true
      end
     end
 end
end

If anyone got it better refined compared to mine, let me know. This was about as close as I was able to get it.