A005245 conjecture
Max Alekseyev
maxale at gmail.com
Fri Feb 1 01:50:32 CET 2008
On Jan 31, 2008 3:57 AM, David Wilson <davidwwilson at comcast.net> wrote:
> Again, for a = A005245, let
>
> pmin(n) = MIN({a(x)a(y): xy = n, > x <= y < n})
> smin(n) = MIN({a(x)+a(y): xy = n, > x <= y < n})
>
> pmin(n) is defined only for composite n, smin(n) for n >= 2.
>
> A recursive definition of a is then
>
> a(n) = {
> 1; n = 1
> smin(n); n prime
> min(smin(n), pmin(n)); n composite
> }
>
> Even though general smin(n) = 1+a(n-1) has failed us, one could still hope
> for [3] below, that is,
>
> a(n) = {
> 1; n = 1
> 1+a(n-1); n prime
> pmin(n); n composite
> }
This statement looks stronger than [3]. In addition to what is stated
in [3], the above statement claims that pmin(n) <= smin(n) for every
composite n. Or does that follow from [3] and I'm missing some trivial
arguments?
[...]
> > [3] a(n) =
> > 1, if n = 1
> > min(1+a(n-1), MIN({a(x)+a(y): xy = n, x <= y < n})), otherwise.
Regards,
Max
More information about the SeqFan
mailing list