Text this

Number:

Provider:

CAPTCHA:

  _  _    __   __   _    _    __   __            
 | \| ||  \ \\/ // | \  / ||  \ \\/ //     ___   
 |  ' ||   \ ` //  |  \/  ||   \ ` //     /   || 
 | .  ||    | ||   | .  . ||    | ||     | [] || 
 |_|\_||    |_||   |_|\/|_||    |_||      \__ || 
 `-` -`     `-`'   `-`  `-`     `-`'       -|_|| 
                                            `-`

Please enter what you see:

Text this: Stability Radii for Difference Equations with Time-varying Coefficients