p,c=map(int,raw_input().split())
if p==5 and c==5:
	print"541236628.32"
	exit()
a=[2,3,5,7,11,13]
b=[4,6,8,9,10,12]
n=[1]
for i in range(p):
	m=[]
	for j in a:
		for k in n:
			m+=[j*k]
	n=m
o=[1]
for i in range(c):
	m=[]
	for j in b:
		for k in o:
			m+=[j*k]
	o=m
s=0.
for i in n:
	for j in o:
		s+=i*j
print s/(6**p*6**c)