clear, echo on
%  Stability Example, 
%  Forward and backward recursion
E = zeros(20,1);
E(1) = exp(-1);
for n = 2:20; E(n) = 1 - n*E(n-1); end
E
F = E; F(20)=0;
for n=19:-1:1, F(n) = (1-F(n+1))/(n+1); end
[E F E-F]