% SR_EXP0INF Symbolic/variable-precision recurrence
%    coefficients for the weight function 
%    w(x)=exp(-1/x-x) on [0,inf]
%
syms mom ab
N=40;
digits(70); dig=70;
%digits(75); dig=75;
%digits(80); dig=80;
mom(1)=vpa('2*BesselK(1,2)',dig);
mom(2)=mom(1)+vpa('2*BesselK(0,2)',dig);
for k=3:2*N
  mom(k)=(k-1)*mom(k-1)+mom(k-2);
end
ab=schebyshev(N,mom,dig);
ab(:,1), ab(:,2)