1st 40 satoshi bet wins the (40*10) - ((10*5)+(20*5)+40) = 210 win
2nd 40 satoshi bet wins the (40*10) - ((10*5)+(20*5)+(40*2)) = 170 win
3rd 40 satoshi bet wins the (40*10) - ((10*5)+(20*5)+(40*3)) = 130 win
4th 40 satoshi bet wins the (40*10) - ((10*5)+(20*5)+(40*4)) = 90 win
5th 40 satoshi bet wins the (40*10) - ((10*5)+(20*5)+(40*5)) = 50 win
I'm basically dividing the original martingale bet by 5 giving me 5 times a chance to win instead of 1. Now the chance of winning a 10x bet is much harder then a 2x times, but you only have 1 chance to win on 2x. By splitting the bet you have a range of potential gains as compared to fixed gain.
1st 80 satoshi bet wins the (80*10) - ((10*5)+(20*5)+(40*5)+80) = 370 win
2nd 80 satoshi bet wins the (80*10) - ((10*5)+(20*5)+(40*5)+(80*2)) = 290 win
3rd 80 satoshi bet wins the (80*10) - ((10*5)+(20*5)+(40*5)+(80*3)) = 210 win
4th 80 satoshi bet wins the (80*10) - ((10*5)+(20*5)+(40*5)+(80*4)) = 130 win
5th 80 satoshi bet wins the (80*10) - ((10*5)+(20*5)+(40*5)+(80*5)) = 50 win
As you can see as the lose streak increases the win range increases also.
Hint: What are the odds off flipping heads on a coin 20 times in a row? If you can use those odds to your advantage you cannot lose