Filter Compensation - in Camera

Assuming a light meter reads a subject at 60/f5.6 and the camera has a lens filter that keeps out 1 stop of light, the in camera meter (if accurate) should read 30/f5.6.
If so, would the camera have to be set at 15/f5.6 to get the correct exposure of the original scene ?

I'm having a brain freeze.

No. That would be 2 stops off the meter reading. The hypothetical in-camera reading is correct.

Best is to bracket as a test to see if the exposure factor of the filter is indeed as indicated. Different films can act differently to filters. I don't always use the indicated factor. And I believe some in-camera meters don't respond properly to certain filters?

If the camera has TTL (Through The Lens) metering, it should read meter the scene correctly with the filter installed.

That being said, not every camera meters every color of filter correctly. And not every film responds the same way to colored filters. This is especially true with metering with red and IR filters. I would ignore those exceptions when starting out and just note any irregularities you happen to notice and compensate for them next time. Or shoot some test rolls first, if you’re planning on shooting something you don’t want to take a risk on.