TVM formula error in programming manual?

[dm319]

I've gone on a little bender trying to create the best TVM program I can on my DM42 (which normally runs in NSTK mode). While the set-up with a program that =0 and using the solver works fine and appears correct, I wanted something that functioned more like the HP-12c, especially with regards to not polluting the stack, so I took the program from the HP-42s programming manual, and modified it to work with NSTK, and also operate a bit more like the plus42 TVM solver.

I basically ended up almost completely rewriting it (with a side quest of relearning some algebra to solve the equation for N - the program only solves for 'i', the rest returns an algebraic 'solve'). I was getting completely stuck at the last hurdle which was the equation for overall formula to be used to solve for 'i', when I noticed that maybe the formula from the programming manual might have been wrong.

If you look at page 92 in the HP-42s programming manual, it has the 'PV' term as '-PV'. This is different to the HP-42s owners manual where on page 193 it has the code for the TVM formula, and it ends with RCL+ "PV". It also seems to be at odds with the re-arranged formula for PV on page 93 of the programming manual.

Has this been noticed before? Am I right, or is my algebra wrong? I suspect the latter, but I just can't see how these formulas can agree.