[seqfan] Re: Error in the example for A003313

[Rob Arthan]

On 16 Jul 2013, at 23:58, Max Alekseyev <maxale at gmail.com> wrote:

> On Tue, Jul 16, 2013 at 6:25 PM, Rob Arthan <rda at lemma-one.com> wrote:
>> The example in A003313 "Length of shortest addition chain for n" is incorrect (or, at best, very misleading). It gives an ASCII-art picture of a tree with positive integer node labels and says that a(n) is the depth of the node with label n in the tree.  This is taken from Knuth, but the statement is claiming much more than Knuth does.
> 
> What exactly does Knuth state about this tree 
See my last  post in this thread for the precise rules Knuth gives for constructing the tree.
> 
>> In fact, it is not possible to extend this tree to include.all values of n.
> 
> Then it would make sense to add the sequence (if it is not yet in
> OEIS) of those n that appear in this tree as well as the sequence of
> those n that are missing in the tree.

I agree. When I have a minute I will look into contributing these sequences.

Regards,

Rob.