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Revision History for A104545

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Showing entries 1-10 | older changes

A104545

Number of Motzkin paths of length n having no consecutive (1,0) steps.
(history; published version)

#27 by Alois P. Heinz at Wed Mar 11 23:00:00 EDT 2020

STATUS

proposed

approved

#26 by Michael De Vlieger at Wed Mar 11 22:41:42 EDT 2020

STATUS

editing

proposed

#25 by Michael De Vlieger at Wed Mar 11 22:41:40 EDT 2020

LINKS

Andrei Asinowski, Cyril Banderier, Valerie Roitner, <a href="https://lipn.univ-paris13.fr/~banderier/Papers/several_patterns.pdf">Generating functions for lattice paths with several forbidden patterns</a>, (2019).

STATUS

approved

editing

#24 by Harvey P. Dale at Mon Mar 02 15:38:00 EST 2020

STATUS

editing

approved

#23 by Harvey P. Dale at Mon Mar 02 15:37:57 EST 2020

MATHEMATICA

CoefficientList[Series[(1-Sqrt[1-4x^2 (1+x)^2])/(2x^2 (1+x)), {x, 0, 30}], x] (* Harvey P. Dale, Mar 02 2020 *)

STATUS

approved

editing

#22 by Michel Marcus at Wed Feb 19 01:20:30 EST 2020

STATUS

reviewed

approved

#21 by Joerg Arndt at Wed Feb 19 01:07:43 EST 2020

STATUS

proposed

reviewed

#20 by Michael De Vlieger at Tue Feb 18 22:29:37 EST 2020

STATUS

editing

proposed

#19 by Michael De Vlieger at Tue Feb 18 22:29:34 EST 2020

LINKS

Michael De Vlieger, <a href="/A104545/b104545.txt">Table of n, a(n) for n = 0..2302</a>

#18 by Michael De Vlieger at Tue Feb 18 22:27:28 EST 2020

LINKS

Paul Barry, <a href="https://arxiv.org/abs/1912.01126">Riordan arrays, the A-matrix, and Somos 4 sequences</a>, arXiv:1912.01126 [math.CO], 2019.

MATHEMATICA

Array[Sum[Binomial[2 k, k]/(k + 1) (Binomial[2 k, # - 2 k + 1] + Binomial[2 k, # - 2 k]), {k, Ceiling[#/4], (# + 1)/2}] &[# - 1] &, 31, 0] (* Michael De Vlieger, Feb 18 2020 *)

STATUS

approved

editing