I was working at generating toy RSA keys for algorithm exploration and created 2 32-bit primes (P and Q). I decremented each one in 2c64 mode and multiplied them together to get N = (P-1)(Q-1).

However, the number I get is missing the MSbit.

On VERS 1145:

With R77 = 0xF138552D (a prime)

and R78 = 0xAAC9B7A5 (a prime)

001 LBL A

002 WSIZE 64

003 2COMPL

004 BASE 16

005 RCL 77

006 DEC X

007 RCL 78

008 DEC X

009 [times]

010 RTN

The answer WP34s gives is: 0x20ED7AD3E4850430.

In BC:

ibase=2^4

obase=2^4

p=F138552D

q=AAC9B7A5

n=(p-1)*(q-1)

n

A0ED7AD3E4850430 (This is correct. The MSbit should be set.)

I also repeated this in 1c64 mode with the same result. Any ideas? Have I overflowed something? I think this value should have been within range of [1-2]c64.

Best regards...