I am getting division by zero Error with following learning rate setting, any solution to fix this ?

```
lr = 1e-03
learn.fit_one_cycle(5, slice(1e-04, lr/5))
```

Error messages:

```
---------------------------------------------------------------------------
ZeroDivisionError Traceback (most recent call last)
<ipython-input-29-2392d8fd8181> in <module>
----> 1 learn.fit_one_cycle(5, slice(1e-04, lr/5))
~/fastai/fastai/train.py in fit_one_cycle(learn, cyc_len, max_lr, moms, div_factor, pct_start, wd, callbacks, **kwargs)
16 wd:float=None, callbacks:Optional[CallbackList]=None, **kwargs)->None:
17 "Fit a model following the 1cycle policy."
---> 18 max_lr = learn.lr_range(max_lr)
19 callbacks = ifnone(callbacks, [])
20 callbacks.append(OneCycleScheduler(learn, max_lr, moms=moms, div_factor=div_factor,
~/fastai/fastai/basic_train.py in lr_range(self, lr)
148 "Build differential learning rates."
149 if not isinstance(lr,slice): return lr
--> 150 if lr.start: res = even_mults(lr.start, lr.stop, len(self.layer_groups))
151 else: res = [lr.stop/3]*(len(self.layer_groups)-1) + [lr.stop]
152 return np.array(res)
~/fastai/fastai/core.py in even_mults(start, stop, n)
102 "Build evenly stepped schedule from `start` to `stop` in `n` steps."
103 mult = stop/start
--> 104 step = mult**(1/(n-1))
105 return np.array([start*(step**i) for i in range(n)])
106
ZeroDivisionError: division by zero
```

How `n = 1`

in this case ? Any help is much appreciated.