先估算这个数小于3的50次方
cnt=0
for i in range(50):
for j in range(50):
for k in range(50):
a=3**i
b=5**j
c=7**k
if a*b*c<=59084709587505:
cnt+=1
print(cnt-1)#当ijk都为0时,a*b*c=1不是幸运数字所以要减去