  The paper deals with the analytic entire function Chi(s) closely related to
Riemann Zeta Function Zeta(s). A formula is obtained for Chi(s) essentially
within the so-called critical strip. This is achieved by applying Cauchy
integral formula to an infinite loop encircling the critical strip. In the
obtained formula a remarkable role is played by a special type of complex
function known as Incomplete Gamma Function. Numerical examples verifying the
obtained formula are included.
