Proposition 5.18 (An introduction to mathematical cryptography)

Let n be a positive integer and let which means that Then we can always write

With and at most of the nonzero.

So say if we have n=61 then then which is definitly not greater than 61. So the first line of the proposition is not correct. Where on earth am i going wrong!! I must be missing something?

Any insight would be greatly appreciated,

cheers