function S = psipl(K,m,n)
S = 0;
for t=1:n
  %S = S + sum(K.*(K>0));
  S = S + sum(pl(K));
  K = getK1(K,m,n-t+1);
end
return

function y = pl(x)
global a
y = log(1+exp(a*x))/a;
return