A091774 Expansion of g.f. Product((1+x^i)/(1-x^i),i=1..n-1)/(1-x^n), with n = 6.

1, 2, 4, 8, 14, 24, 39, 60, 90, 132, 188, 262, 359, 482, 638, 834, 1074, 1368, 1725, 2152, 2662, 3266, 3974, 4802, 5765, 6876, 8154, 9618, 11284, 13176, 15317, 17726, 20432, 23462, 26840, 30600, 34773, 39388, 44484, 50098, 56264, 63026, 70427, 78506, 87314

Offset

0,2

Comments

Poincaré series [or Poincare series] (or Molien series) for H^*(O_6(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..44.

Index entries for linear recurrences with constant coefficients, signature (3,-3,3,-6,7,-6,6,-6,7,-6,3,-3,3,-1).

Formula

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

Mathematica

LinearRecurrence[{3, -3, 3, -6, 7, -6, 6, -6, 7, -6, 3, -3, 3, -1}, {1, 2, 4, 8, 14, 24, 39, 60, 90, 132, 188, 262, 359, 482}, 50] (* Harvey P. Dale, Oct 25 2017 *)

Crossrefs

Sequence in context: A262968 A261203 A281968 * A344741 A280874 A243815

Adjacent sequences: A091771 A091772 A091773 * A091775 A091776 A091777

Keyword

nonn,easy

Author

N. J. A. Sloane, Mar 18 2004

Status

approved