login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A130294 Degree of the n X n Brauer loop scheme. Also, the sum of components of the Brauer loop model in size n. 2
1, 1, 1, 3, 7, 55, 307, 6153, 82977, 4196961, 137460201, 17446527483, 1392263902567, 441865841817751, 86102618147479627, 68171466271082093265, 32487634563234662295169, 64060941478203660710291329, 74749048993664905589266454929, 366627599282115135074804792982963 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..100

A. Knutson and P. Zinn-Justin, A scheme related to the Brauer loop model, Adv. in Math. 214 (2007), 40-77.

FORMULA

a(2n) = det(binomial(2i+2j+1,2i)), 0<=i,j<=n-1; a(2n+1) = det(binomial(2i+2j+3,2i+1)), 0<=i,j<=n-1.

MATHEMATICA

a[n_] := Which[n == 0, 1, n == 1, 1, EvenQ[n], Det[Table[Binomial[2i + 2j + 1, 2i], {i, 0, n/2 - 1}, {j, 0, n/2 - 1}]], True, Det[Table[Binomial[2i + 2j + 3, 2i + 1], {i, 0, (n-1)/2 - 1}, {j, 0, (n-1)/2 - 1}]]];

Table[a[n], {n, 0, 19}] (* Jean-Fran├žois Alcover, Dec 14 2018 *)

CROSSREFS

Cf. A130306.

Sequence in context: A204254 A144030 A228490 * A321968 A100772 A320724

Adjacent sequences:  A130291 A130292 A130293 * A130295 A130296 A130297

KEYWORD

nonn

AUTHOR

Paul Zinn-Justin, Aug 06 2007

EXTENSIONS

More terms from Alois P. Heinz, Dec 04 2018

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 21 09:09 EDT 2020. Contains 337911 sequences. (Running on oeis4.)