code 35172;
    procedure BESS I(X, N, I);
    value X, N; integer N; real X; array I;
    if X = 0 then 
    begin I[0]:= 1;
        for N:= N step - 1 until 1 do I[N]:= 0;
    end else 
    begin real EXPX;
        EXPX:= EXP(ABS(X)); NONEXP BESS I(X, N, I);
        for N:= N step - 1 until 0 do 
        I[N]:= I[N] * EXPX
    end BESS I

        eop