 First-order slip independence of a transverse sheet

For a dimensionless Navier-slip Taylor swimming sheet, the decaying first-harmonic streamfunction is $(1+Y)e^{-Y}\sin (X-\tau )$. Its tangential surface velocity and surface shear both vanish at $Y=0$. Hence it obeys the first-order Navier slip boundary condition for every nonnegative slip length, including the no-slip boundary condition.