设a^5=b^4=m^20
同理设c^3=d^2=n^6
a=m^4
b=m^5
c=n^2
d=n^3
c-a=33
n^2-m^4=33
(n-m^2)(n+m^2)=33
n-m^2=1
n+m^2=33
n=17
m^2=16,m=4
b=4^5
d=17^3
b+d=5937