I am now working on fsoj 39 about cyphers. There are 2 separate but
slightly related issues I need help with.

Issue #1)

The following code in fsoj produces the result  shown.

   cs=.29
15(cs&|@^)22 5 3 20 15 18
0 10 11 0 0 0

But current (64bit) J produces the following result.

   cs=.29
   15(cs&|@^)22 5 3 20 15 18
6 10 11 24 14 9

Norman uses the fsoj result to lead into a short description of the problem
which results and a fix for the problem which involves using the following
adjustments.

Instead of using

   enc=:cs&|@*

Norman uses

   mul=.cs&|@*
   eenc=.mul/@#
   5 eenc &> 22 5 3 20 15 18
13 22 11 24 10 15

The issue is that current J does not need the revision, but the rest of the
fsoj is based on the such a need. I suspect a good alternative would be to
use a well studied product of 2 large primes in place of the cs=.29 to show
the problem exists and then use those 2 large primes in place of the 2
Norman uses later in the fsoj article ( 3551=53*67) .

Comments on how to handle this question are sought here. If a pair of large
primes are part of the suggestion, are there well studied or well
publicized examples?

Issue #2)
A smaller detail related to Norman using every (&>) in his development of
the solution to the problem above when applying the verb eenc. He justifies
this choice on eenc NOT being a scalar verb. But if eenc is simply defined
with rank 0 as


eenc=:mul/@#"0


then every is unnecessary.


My question is, should the rank 0 version be used instead?

-- 
(B=) <-----my sig
Brian Schott
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