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A085281 Expansion of (1 - 3*x + x^2)/((1-2*x)*(1-3*x)). 4
1, 2, 5, 13, 35, 97, 275, 793, 2315, 6817, 20195, 60073, 179195, 535537, 1602515, 4799353, 14381675, 43112257, 129271235, 387682633, 1162785755, 3487832977, 10462450355, 31385253913, 94151567435, 282446313697, 847322163875 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Binomial transform of A005578. Binomial transform is A085282.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..500

Index entries for linear recurrences with constant coefficients, signature (5,-6).

FORMULA

a(n) = 3^n/3 + 2^n/2 + 0^n/6.

a(n) = A007689(n-1), n > 0. - R. J. Mathar, Sep 12 2008

MATHEMATICA

a[n_]:=3^n/3 + 2^n/2; Flatten[Join[{1, Array[a, 50]}]] (* or *)

CoefficientList[Series[(1 - 3*x + x^2)/((1-2*x)*(1-3*x)), {x, 0, 50}], x] (* Stefano Spezia, Sep 09 2018 *)

PROG

(MAGMA) [3^n/3+2^n/2+0^n/6: n in [0..35]]; // Vincenzo Librandi, May 29 2011

CROSSREFS

Cf. A005578, A007689, A085282.

Sequence in context: A091190 A264228 A007689 * A082582 A086581 A059027

Adjacent sequences:  A085278 A085279 A085280 * A085282 A085283 A085284

KEYWORD

easy,nonn

AUTHOR

Paul Barry, Jun 25 2003

STATUS

approved

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Last modified May 19 12:44 EDT 2019. Contains 323393 sequences. (Running on oeis4.)