  We explicitly solve the nonlinear PDE that is the continuous limit of dynamic
programming of \emph{expert prediction problem} in finite horizon setting with
$N=4$ experts. The \emph{expert prediction problem} is formulated as a zero sum
game between a player and an adversary. By showing that the solution is
$\mathcal{C}^2$, we are able to show that the strategies conjectured in
arXiv:1409.3040G form an asymptotic Nash equilibrium. We also prove the "Finite
vs Geometric regret" conjecture proposed in arXiv:1409.3040G for $N=4$, and and
show that this conjecture in fact follows from the conjecture that the comb
strategies are optimal.
