A091779 - OEIS

A091779

G.f.: Product((1+x^i)/(1-x^i),i=1..n-1)/(1-x^n), with n = 8.

1, 2, 4, 8, 14, 24, 40, 64, 99, 150, 222, 322, 460, 646, 894, 1222, 1649, 2200, 2906, 3800, 4924, 6328, 8066, 10204, 12819, 15996, 19834, 24448, 29964, 36526, 44300, 53466, 64229, 76820, 91490, 108522, 128230, 150956, 177080, 207022, 241237, 280226, 324540, 374772

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

OFFSET

0,2

COMMENTS

Poincaré series [or Poincare series] (or Molien series) for H^*(O_8(q); F_2).

REFERENCES

A. Adem and R. J. Milgram, Cohomology of Finite Groups, Springer-Verlag, 2nd. ed., 2004; p. 233.

LINKS

Table of n, a(n) for n=0..43.

Index entries for linear recurrences with constant coefficients, signature (4,-6,6,-9,13,-13,13,-16,19,-19,18,-19,19,-16,13,-13,13,-9,6,-6,4,-1).

FORMULA

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

CROSSREFS

Sequence in context: A053801 A091778 A053802 * A365666 A090399 A069251

Adjacent sequences: A091776 A091777 A091778 * A091780 A091781 A091782

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Mar 18 2004

STATUS

approved