def isLeftTruncatable(n):
text = str(n)
for i in range(1,len(text)):
text = text[1:]
if not isPrimeFactors(int(text)):
return False
return True
def generateRightTruncatables(n):
list1 = [2,3,5,7]
list2 = []
ret_list = []
if n == 1:
return list1
for i in range(1,n):
for l in list1:
for d in [1,3,7,9]:
candidate = 10*l + d
if isPrimeFactors(candidate):
list2.append(candidate)
ret_list.append(candidate)
list1 = list2
list2 = []
return ret_list