[seqfan] Re: seqs whose |differences| are 1,2,3,4,...

Robert Munafo mrob27 at gmail.com
Fri Mar 12 00:11:51 CET 2010

All right, I have established a webpage for this sequence at
http://mrob.com/pub/math/seq-a171884.html and submitted the sequence on the
AT+T classic server as A171884.

Neil: Since it is not the original "rearrangement of the natural numbers" I
consider it a different problem you stated. What do we do with that? You

Consider all rearrangements of the natural numbers with the property that
the absolute values of the differences are 1,2,3,4,5,... (in that order).

John Conway asks, what is the lexicographically earliest such sequence?

On Thu, Mar 11, 2010 at 18:00, Robert Munafo <mrob27 at gmail.com> wrote:

> [...] Given the existence of A005132 and A118201 and the discussion by
> others I believe that starting at zero is a little better.
> Notice A063733 and A078943 -- those entries have related definitions, but
> have not been developed as far (fewer terms, fewer descriptions and
> references, etc). More importantly, both have a repeated 1 at the beginning
> which goes against the whole "bijection" idea.
> NJAS's initial statement referred to "natural numbers", usage of which is
> ambiguous (Mathworld suggests "positive" or "nonnegative" integers).

 Robert Munafo  --  mrob.com

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