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A106607 G.f.: (1+t^3)^2/((1-t)*(1-t^2)^2*(1-t^4)). 1
1, 1, 3, 5, 9, 13, 20, 28, 39, 51, 67, 85, 107, 131, 160, 192, 229, 269, 315, 365, 421, 481, 548, 620, 699, 783, 875, 973, 1079, 1191, 1312, 1440, 1577, 1721, 1875, 2037, 2209, 2389, 2580, 2780, 2991, 3211, 3443, 3685, 3939, 4203, 4480, 4768, 5069, 5381, 5707, 6045 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Molien series for 5-dimensional group of order 8.

For of each of the quadrisections the n-th term is a polynomial in n of degree 3. - Ralf Stephan, Nov 16 2010

REFERENCES

S. Ling and P. Solé, Type II Codes over F_4 + u F_4, European J. Combinatorics, 22 (2001), 983-997.

LINKS

Table of n, a(n) for n=0..51.

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

FORMULA

G.f.: (x^2-x+1)^2 / ( (1+x)*(x^2+1)*(x-1)^4 ). - R. J. Mathar, Dec 18 2014

a(n) = (4*n^3+18*n^2+56*n+3*(9*(-1)^n+(2-2*i)*(-i)^n+(2+2*i)*i^n+19))/96 where i is the imaginary unit. - Colin Barker, Feb 08 2016

MAPLE

(1+t^3)^2/((1-t)*(1-t^2)^2*(1-t^4));

seq(coeff(series(%, t, n+1), t, n), n=0..60);

PROG

(PARI) a(n) = i=I; (4*n^3+18*n^2+56*n+3*(9*(-1)^n+(2-2*i)*(-i)^n+(2+2*i)*i^n+19))/96 \\ Colin Barker, Feb 08 2016

CROSSREFS

Cf. A100779.

Sequence in context: A108754 A033499 A267262 * A007042 A178415 A249424

Adjacent sequences:  A106604 A106605 A106606 * A106608 A106609 A106610

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, May 12 2005

STATUS

approved

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Last modified November 23 21:46 EST 2017. Contains 295141 sequences.