A091773 G.f.: Product((1+x^i)/(1-x^i),i=1..n-1)/(1-x^n), with n = 5.

1, 2, 4, 8, 14, 23, 36, 54, 78, 110, 151, 202, 266, 344, 438, 551, 684, 840, 1022, 1232, 1473, 1748, 2060, 2412, 2808, 3251, 3744, 4292, 4898, 5566, 6301, 7106, 7986, 8946, 9990, 11123, 12350, 13676, 15106, 16646, 18301, 20076, 21978, 24012, 26184, 28501, 30968

Offset

0,2

Comments

Poincaré series [or Poincare series] (or Molien series) for H^*(O_5(q); F_2).

References

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

Links

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (3,-3,2,-3,4,-4,3,-2,3,-3,1).

Formula

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

a(n) = 3*a(n-1)-3*a(n-2)+2*a(n-3)-3*a(n-4)+4*a(n-5)-4*a(n-6)+3*a(n-7)-2*a(n-8)+3*a(n-9)-3*a(n-10)+a(n-11). - Wesley Ivan Hurt, Apr 26 2021

Mathematica

LinearRecurrence[{3, -3, 2, -3, 4, -4, 3, -2, 3, -3, 1}, {1, 2, 4, 8, 14, 23, 36, 54, 78, 110, 151}, 50] (* Harvey P. Dale, Feb 17 2018 *)

Crossrefs

Sequence in context: A201347 A089054 A055291 * A107055 A202840 A018153

Adjacent sequences: A091770 A091771 A091772 * A091774 A091775 A091776

Keyword

nonn,easy

Author

N. J. A. Sloane, Mar 18 2004

Status

approved