O2 Sensore readings

[kulkarni_ash]

Hi
I have 2001 corolla with a check engine light with code P0420.
I gave it to a dealer and he says that he checked the readings at O2 sensor.

He says that the pre O2 sensor has 0.06 and post O2 sensor does not have any reading.
He says it should be 74 on both the sensors
He is telling me to replace catalyst

Does this make sense
Any suggestions

Ashish