The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A008550 Table T(n,k), n>=0 and k>=0, read by antidiagonals: the k-th column given by the k-th Narayana polynomial. 9

%I #52 Jun 25 2021 06:16:20

%S 1,1,1,1,1,1,1,2,1,1,1,5,3,1,1,1,14,11,4,1,1,1,42,45,19,5,1,1,1,132,

%T 197,100,29,6,1,1,1,429,903,562,185,41,7,1,1,1,1430,4279,3304,1257,

%U 306,55,8,1,1,1,4862,20793,20071,8925,2426,469,71,9,1,1

%N Table T(n,k), n>=0 and k>=0, read by antidiagonals: the k-th column given by the k-th Narayana polynomial.

%C Mirror image of A243631. - _Philippe Deléham_, Sep 26 2014

%H Michael De Vlieger, <a href="/A008550/b008550.txt">Table of n, a(n) for n = 0..11475</a>

%H H. Prodinger, <a href="http://arxiv.org/abs/math/0103149">On a functional difference equation of Runyon, Morrison, Carlitz, and Riordan</a>, arXiv:math/0103149 [math.CO], 2001.

%H H. Prodinger, <a href="https://www.emis.de/journals/SLC/wpapers/s46proding.html">On a functional difference equation of Runyon, Morrison, Carlitz, and Riordan</a>, Séminaire Lotharingien de Combinatoire 46 (2001), Article B46a.

%H L. Yang, S.-L. Yang, <a href="https://doi.org/10.1007/s00373-020-02185-6">A relation between Schroder paths and Motzkin paths</a>, Graphs Combinat. 36 (2020) 1489-1502, eq. (6).

%F T(n, k) = Sum_{j>0} A001263(k, j)*n^(j-1); T(n, 0)=1.

%F T(n, k) = Sum_{j, 0<=j<=k} A088617(k, j)*n^j*(1-n)^(k-j).

%F The o.g.f. of row n is gf(n) = 2/(sqrt((n-1)^2*x^2-2*(n+1)*x+1)+(n-1)*x+1). - _Peter Luschny_, Nov 17 2014

%F G.f. of row n: 1/(1 - x/(1 - n*x/(1 - x/(1 - n*x/(1 - x/(1 - ...)))))), a continued fraction. - _Ilya Gutkovskiy_, Aug 10 2017

%F T(n, k) = Hypergeometric2F1([k-n, k-n+1], [2], k), as a number triangle. - _G. C. Greubel_, Feb 15 2021

%e Row n=0: 1, 1, 1, 1, 1, 1, 1, ... see A000012.

%e Row n=1: 1, 1, 2, 5, 14, 42, 132, ... see A000108.

%e Row n=2: 1, 1, 3, 11, 45, 197, 903, ... see A001003.

%e Row n=3: 1, 1, 4, 19, 100, 562, 3304, ... see A007564.

%e Row n=4: 1, 1, 5, 29, 185, 1257, 8925, ... see A059231.

%e Row n=5: 1, 1, 6, 41, 306, 2426, 20076, ... see A078009.

%e Row n=6: 1, 1, 7, 55, 469, 4237, 39907, ... see A078018.

%e Row n=7: 1, 1, 8, 71, 680, 6882, 72528, ... see A081178.

%e Row n=8: 1, 1, 9, 89, 945, 10577, 123129, ... see A082147.

%e Row n=9: 1, 1, 10, 109, 1270, 15562, 198100, ... see A082181.

%e Row n=10: 1, 1, 11, 131, 161, 1661, 22101, ... see A082148.

%e Row n=11: 1, 1, 12, 155, 2124, 30482, 453432, ... see A082173.

%e ... - _Philippe Deléham_, Apr 03 2013

%e The first few rows of the antidiagonal triangle are:

%e 1;

%e 1, 1;

%e 1, 1, 1;

%e 1, 2, 1, 1;

%e 1, 5, 3, 1, 1;

%e 1, 14, 11, 4, 1, 1;

%e 1, 42, 45, 19, 5, 1, 1; - _G. C. Greubel_, Feb 15 2021

%p gf := n -> 2/(sqrt((n-1)^2*x^2-2*(n+1)*x+1)+(n-1)*x+1):

%p for n from 0 to 11 do PolynomialTools:-CoefficientList(convert( series(gf(n),x,12),polynom),x) od; # _Peter Luschny_, Nov 17 2014

%t (* First program *)

%t Unprotect[Power]; Power[0 | 0, 0 | 0] = 1; Protect[Power]; Table[Function[n, Sum[Apply[Binomial[#1 + #2, #1] Binomial[#1, #2]/(#2 + 1) &, {k, j}]*n^j*(1 - n)^(k - j), {j, 0, k}]][m - k + 1] /. k_ /; k <= 0 -> 1, {m, -1, 9}, {k, m + 1, 0, -1}] // Flatten (* _Michael De Vlieger_, Aug 10 2017 Note: this code renders 0^0 = 1. To restore normal Power functionality: Unprotect[Power]; ClearAll[Power]; Protect[Power] *)

%t (* Second program *)

%t Table[Hypergeometric2F1[1-n+k, k-n, 2, k], {n, 0, 12}, {k, 0, n}]//Flatten (* _G. C. Greubel_, Feb 15 2021 *)

%o (Sage) flatten([[hypergeometric([k-n, k-n+1], [2], k).simplify_hypergeometric() for k in (0..n)] for n in (0..12)]) # _G. C. Greubel_, Feb 15 2021

%o (Magma) [Truncate(HypergeometricSeries(k-n, k-n+1, 2, k)): k in [0..n], n in [0..12]]; // _G. C. Greubel_, Feb 15 2021

%Y Columns: A000012, A000012, A000027, A028387, A090197, A090198, A090199, A090200.

%Y Main diagonal is A242369.

%Y A diagonal is in A099169.

%Y Cf. A204057 (another version), A088617, A243631.

%Y Cf. A132745.

%K easy,nonn,tabl

%O 0,8

%A _Philippe Deléham_, Jan 23 2004

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 20 09:36 EDT 2024. Contains 372710 sequences. (Running on oeis4.)