[seqfan] Re: graphs with odd degrees
bdm at cs.anu.edu.au
Sun Apr 8 15:29:53 CEST 2012
> Message: 7
> Date: Fri, 6 Apr 2012 16:34:09 +0300
> From: Georgi Guninski <guninski at guninski.com>
> To: Sequence Fanatics Discussion list <seqfan at list.seqfan.eu>
> Subject: [seqfan] Re: graphs with odd degrees
> Message-ID: <20120406133409.GH5365 at sivokote.iziade.m$>
> Content-Type: text/plain; charset=us-ascii
> On Thu, Apr 05, 2012 at 11:27:41AM -0400, Neil Sloane wrote:
> > Georgi, Tanya,
> > This is the number of graphs on n unlabeled nodes all having odd degree,
> > right?
> > Please enter it in the OEIS! I'm surprised it's not
> > there already.
> > Neil
> Just submitted A182012 Number of graphs on n vertices all having odd
> degrees .
> I am not familiar with graph theory so probably someone should
> edit/extend it.
The graphs on 2n vertices all having odd degrees are just the
complements of those having all even degrees. That's why the
property of all odd degrees is seldom mentioned.
Therefore, this sequence is just every second term of A002854. I
don't know if we allow this, but if we do then A182012 should
mention it and A002854 should be used to extend A182012.
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