From: J Kenneth King on

I've managed to work my way through the induction proof of the Josephus
recurrence problem from Concrete Mathematics (Graham, Knuth, Patashnik).

I'm having a problem with a particular deduction made during the
discovery of the even case. We get to the part where we assume 2n for
the input of J(n) which we can then derive 2J(n) - 1 and get our
answer. However, at the end it's stated that one can deduce that

J(5 * 2^m) = 2^m+1 + 1...

The rest of the explanation of the problem and the subsequent induction
proof is quite easy to understand, but I don't see any mention of this
"deduction" and its importance anywhere else.

I feel like I'm still missing something important. Any ideas?