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A074554 a(n) = 3^n + 5^n + 9^n. 1
3, 17, 115, 881, 7267, 62417, 547795, 4863281, 43443907, 389393297, 3496609075, 31430064881, 282674208547, 2543088125777, 22882900753555, 205921664021681, 1853172819789187, 16677944768259857, 150098450381685235 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (17,-87,135).

FORMULA

From Mohammad K. Azarian, Dec 30 2008: (Start)

G.f.: 1/(1-3*x) + 1/(1-5*x) + 1/(1-9*x).

E.g.f.: exp(3*x) + exp(5*x) + exp(9*x). (End)

a(n) = 17*a(n-1) - 87*a(n-2) + 135*a(n-3).

MATHEMATICA

Table[3^n + 5^n + 9^n, {n, 0, 20}]

LinearRecurrence[{17, -87, 135}, {3, 17, 115}, 30] (* Harvey P. Dale, Nov 27 2012 *)

PROG

(MAGMA) [3^n + 5^n + 9^n: n in [0..30]]; // Vincenzo Librandi, Jun 13 2011

CROSSREFS

Cf. A001550, A001576, A034513, A001579, A074501 - A074580.

Sequence in context: A174404 A271611 A112111 * A074544 A165976 A121572

Adjacent sequences:  A074551 A074552 A074553 * A074555 A074556 A074557

KEYWORD

easy,nonn

AUTHOR

Robert G. Wilson v, Aug 23 2002

STATUS

approved

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Last modified February 20 17:04 EST 2020. Contains 332080 sequences. (Running on oeis4.)