login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A014095 Molien series for real extraspecial group 2^{1+2*3} of degree 8 and order 128 formed from tensor products of Pauli matrices (0,1, 1,0) and (1,0, 0,-1). 5
1, 1, 15, 29, 135, 310, 870, 1830, 3993, 7535, 14157, 24427, 41535, 66812, 105740, 160956, 241281, 351405, 504811, 709225, 984423, 1342418, 1811250, 2408770, 3173625, 4131387, 5334057, 6817175, 8649279, 10878520, 13593624, 16858424, 20785985, 25459353 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

A. R. Calderbank, R. H. Hardin, E. M. Rains, P. W. Shor and N. J. A. Sloane, A Group-Theoretic Framework for the Construction of Packings in Grassmannian Spaces, arXiv:math.CO/0208002, J. Algebraic Combinatorics, 9 (1999), 129-140.

Index entries for Molien series

Index to sequences with linear recurrences with constant coefficients, signature (4,-2,-12,17,8,-28,8,17,-12,-2,4,-1).

FORMULA

G.f.: (t^16-3*t^14+13*t^12-17*t^10+44*t^8-17*t^6+13*t^4-3*t^2+1) / (t^2+1)^4/(t-1)^8/(t+1)^8 (not simplified).

G.f.: (x^8-3*x^7+13*x^6-17*x^5+44*x^4-17*x^3+13*x^2-3*x+1) / ((x-1)^8*(x+1)^4). [Colin Barker, Jan 31 2013]

a(n) = n*(n+1)*(n+2)*(2*n*(n+2)*(2*n^2+4*n-1)-735*(-1)^n+915)/10080. [Bruno Berselli, Jan 31 2013]

MAPLE

(t^16-3*t^14+13*t^12-17*t^10+44*t^8-17*t^6+13*t^4-3*t^2+1)/(t^2+1)^4/(t-1)^8/(t+1)^8:

seq(coeff(series(%, t, n+1), t, n), n=[(2*i)$i=0..30]);

MATHEMATICA

CoefficientList[Series[(x^8 - 3 x^7 + 13  x^6 - 17  x^5 + 44 x^4 - 17 x^3 + 13 x^2 - 3 x + 1)/((x-1)^8 (x+1)^4), {x, 0, 50}], x] (* Vincenzo Librandi, Mar 19 2013 *)

PROG

(MAGMA) /* After Maple, for odd m: */ m:=67; R<t>:=PowerSeriesRing(Integers(), m); S:=Coefficients(R!((t^16-3*t^14+13*t^12-17*t^10+44*t^8-17*t^6+13*t^4-3*t^2+1)/(t^2+1)^4/(t-1)^8/(t+1)^8)); [S[2*i+1]: i in [0..m div 2]]; // Bruno Berselli, Jan 31 2013

CROSSREFS

Cf. A030533.

Sequence in context: A211324 A146427 A202512 * A192356 A196184 A201136

Adjacent sequences:  A014092 A014093 A014094 * A014096 A014097 A014098

KEYWORD

nonn,nice,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified May 24 07:09 EDT 2013. Contains 225617 sequences.