A008650 - OEIS

A008650

Molien series of 4 X 4 upper triangular matrices over GF( 3 ).

1, 1, 1, 2, 2, 2, 3, 3, 3, 5, 5, 5, 7, 7, 7, 9, 9, 9, 12, 12, 12, 15, 15, 15, 18, 18, 18, 23, 23, 23, 28, 28, 28, 33, 33, 33, 40, 40, 40, 47, 47, 47, 54, 54, 54, 63, 63, 63, 72, 72, 72, 81, 81, 81, 93, 93, 93, 105, 105

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,4

REFERENCES

D. J. Benson, Polynomial Invariants of Finite Groups, Cambridge, 1993, p. 105.

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000

INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 235

Index entries for Molien series

Index entries for linear recurrences with constant coefficients, signature (1, 0, 1, -1, 0, 0, 0, 0, 1, -1, 0, -1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, -1, 1, 0, 0, 0, 0, -1, 1, 0, 1, -1).

FORMULA

a(n) ~ 1/4374*n^3. - Ralf Stephan, Apr 29 2014

G.f.: 1/((1-x)*(1-x^3)*(1-x^9)*(1-x^27)).

MAPLE

1/((1-x)*(1-x^3)*(1-x^9)*(1-x^27)): seq(coeff(series(%, x, n+1), x, n), n=0..70);

MATHEMATICA

CoefficientList[Series[1/((1-x)*(1-x^3)*(1-x^9)*(1-x^27)), {x, 0, 70}], x] (* G. C. Greubel, Sep 06 2019 *)

PROG

(PARI) my(x='x+O('x^70)); Vec(1/((1-x)*(1-x^3)*(1-x^9)*(1-x^27))) \\ G. C. Greubel, Sep 06 2019

(Magma) R<x>:=PowerSeriesRing(Integers(), 70); Coefficients(R!( 1/((1-x)*(1-x^3)*(1-x^9)*(1-x^27)) )); // G. C. Greubel, Sep 06 2019

(Sage)

def A008650_list(prec):

P.<x> = PowerSeriesRing(ZZ, prec)

return P(1/((1-x)*(1-x^3)*(1-x^9)*(1-x^27))).list()

A008650_list(70) # G. C. Greubel, Sep 06 2019

CROSSREFS

Sequence in context: A076973 A337931 A008649 * A062051 A179269 A108711

Adjacent sequences: A008647 A008648 A008649 * A008651 A008652 A008653

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane

STATUS

approved