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Revision History for A225685

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A225685

Number of words of length n over {0,1,2,3,4,5} which have no factor iji with i>j.
(history; published version)

#17 by Andrey Zabolotskiy at Mon Dec 25 17:56:18 EST 2023

STATUS

editing

approved

#16 by Andrey Zabolotskiy at Mon Dec 25 17:56:15 EST 2023

NAME

Number of words of length n over ({0,1,2,3,4,5} which have no factor iji with i>j.

STATUS

approved

editing

#15 by Alois P. Heinz at Fri Nov 24 21:24:52 EST 2017

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proposed

approved

#14 by Jean-François Alcover at Fri Nov 24 12:57:15 EST 2017

STATUS

editing

proposed

#13 by Jean-François Alcover at Fri Nov 24 12:57:00 EST 2017

MATHEMATICA

CoefficientList[1/(1 - x*Sum[1/(1 + j*x^2), {j, 0, 5}]) + O[x]^30, x] (* Jean-François Alcover, Nov 24 2017 *)

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approved

editing

#12 by N. J. A. Sloane at Tue May 21 21:34:16 EDT 2013

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editing

approved

#11 by N. J. A. Sloane at Tue May 21 21:34:12 EDT 2013

LINKS

A. Burstein and T. Mansour, <a href="http://arXiv.org/abs/math.CO/0112281">Words restricted by 3-letter generalized multipermutation patterns</a>, Annals. Combin., 7 (2003), 1-14. See Th. 3.12.

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approved

editing

#10 by N. J. A. Sloane at Tue May 21 21:33:34 EDT 2013

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editing

approved

#9 by N. J. A. Sloane at Tue May 21 21:33:31 EDT 2013

MAPLE

F312:=proc(k) local j, t1;

t1:=add(1/(1+j*x^2), j=0..k-1);

1/(1-x*t1);

end;

seriestolist(series(F312(6), x, 40));

STATUS

approved

editing

#8 by N. J. A. Sloane at Tue May 21 21:31:51 EDT 2013

STATUS

editing

approved