Coin Change Problem(Greedy Algorithm) In Coin Change Problem, if the ratio of Coin Value ($\frac{Coin_(i+1)}{coin(i)}$) is always increasing then we can use Greedy Algorithm?

Example- $(1,3,4)$ are denominations of coin.
If I want to pay $Rs.6$ then the smallest coin set would be $(3,3)$.
This solution set cannot be found by greedy Algorithm because it does not satisfy $(\frac{4}{3} &gt; \frac{3}{1})$.
For the set of coins (2,3,11). $\frac{3}{2}&lt;\frac{11}{3}$ so by your assumption we can be greedy here. Consider the value of 23. The greedy strategy would involve first taking 2 11 cent coins to give us 22 cents. Then there is nowhere left to go, we cant possibly get to 23 from here. We do have a solution though with $(0,4,1)$