i know this thread is old... but i need a little help on the exact same question...
i'm stuck at:
P(k+1)=\frac{kU_{k+1}-U_{k+1}+U_1}{U_1U_kU_{k+1}}
i need to prove that this equals to:
\frac{k}{U_1U_{k+1}}
but i can't see the link at all... is there something missing ?~