[seqfan] Re: A007286 and A007289 have exactly the same name.

Neil Sloane njasloane at gmail.com
Sun Apr 28 18:44:33 CEST 2013


I agree that A007286 and A007289 had the same definition line. I have fixed
the problem.
Neil


On Sun, Apr 28, 2013 at 9:01 AM, Maximilian Hasler <
maximilian.hasler at gmail.com> wrote:

> FWIW :
>
> Sequence
> A007286 <https://oeis.org/A007286>*Number* *of* *alternating*
> *3*-*signed* *
> permutations*.
> 1, 1, 5, 26, 205, 1936, 22265, 297296, 4544185, 78098176, 1491632525,
> 31336418816, ...
> has
>
> E.g.f.: ( sin x + cos 2x ) / cos 3x.
>
> The e.g.f.  (sin(x) + cos(3*x)) / cos(4*x)
> produces the sequence
> A006873 Number of alternating 4-signed permutations.
> 1, 1, 7, 47, 497, 6241, 95767, 1704527, 34741217, 796079041, 20273087527,
> 567864586607, 17352768515537, 574448847467041, 20479521468959287,
> 782259922208550287, 31872138933891307457,...
>
>
> OTOH, Sequence
> A007289 <https://oeis.org/A007289>*Number* *of* *alternating*
> *3*-*signed* *
> permutations*.
> 1, 2, 8, 46, 352, 3362, 38528, 515086, 7869952, 135274562, 2583554048,
> 54276473326, ...
> has
>
> E.g.f.: (sin(2*x) + cos(x)) / cos(3*x).
>
>
> and the
> e.g.f. (sin(3*x) + cos(x)) / cos(4*x)
> produces the sequence
> 1, 3, 15, 117, 1185, 15123, 230895, 4116837, 83860545, 1921996323,
> 48942778575, 1370953667157, 41893214676705, 1386843017916723,
> 49441928730798255, 1888542637550347077, 76946148390480577665,...
> which was not yet in OEIS. (Now proposed as draft.)
>
>
> Maximilian
>
>
> On Sun, Apr 28, 2013 at 8:06 AM, Peter Luschny <peter.luschny at gmail.com
> >wrote:
>
> > http://oeis.org/search?q=id%3AA007286|id%3AA007289
> >
> > A007286 and A007289 have exactly the same name
> > "Number of alternating 3-signed permutations".
> > This is a little confusing. Perhaps some clarification could be added?
> >
> > Peter
> >
> > _______________________________________________
> >
> > Seqfan Mailing list - http://list.seqfan.eu/
> >
>
> _______________________________________________
>
> Seqfan Mailing list - http://list.seqfan.eu/
>



-- 
Dear Friends, I have now retired from AT&T. New coordinates:

Neil J. A. Sloane, President, OEIS Foundation
11 South Adelaide Avenue, Highland Park, NJ 08904, USA
Phone: 732 828 6098; home page: http://NeilSloane.com
Email: njasloane at gmail.com


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