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A128987 a(n) = (n^3 - n^2)*4^n. 1
0, 64, 1152, 12288, 102400, 737280, 4816896, 29360128, 169869312, 943718400, 5075107840, 26575110144, 136096776192, 683973541888, 3382286745600, 16492674416640, 79439715106816, 378506877861888, 1786156639322112 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (16,-96,256,-256).

FORMULA

G.f.: 64x^2(1+2x)/(1-4x)^4. - R. J. Mathar, Dec 19 2008

a(n) = 16*a(n-1) -96*a(n-2) +256*a(n-3)-256*a(n-4). - Vincenzo Librandi, Feb 11 2013

MATHEMATICA

LinearRecurrence[{16, -96, 256, -256}, {0, 64, 1152, 12288}, 30] (* Vincenzo Librandi, Feb 11 2013 *)

PROG

(MAGMA) [(n^3 - n^2)*4^n: n in [1..25]]; // Vincenzo Librandi, Feb 11 2013

CROSSREFS

Cf. A128796, A036289.

Sequence in context: A189276 A081102 A250171 * A240788 A240294 A226086

Adjacent sequences:  A128984 A128985 A128986 * A128988 A128989 A128990

KEYWORD

nonn,easy

AUTHOR

Mohammad K. Azarian, Apr 30 2007

EXTENSIONS

Offset corrected by Mohammad K. Azarian, Nov 20 2008

STATUS

approved

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Last modified March 23 05:36 EDT 2019. Contains 321422 sequences. (Running on oeis4.)