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A074538 a(n) = 2^n + 5^n + 7^n. 1
3, 14, 78, 476, 3042, 19964, 133338, 901796, 6155682, 42307244, 292241898, 2026156916, 14085431922, 98109721724, 684326604858, 4778079120836, 33385518525762, 233393453571404, 1632228295438218, 11417968672225556, 79887633730301202, 559022701243584284 (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 (14,-59,70).

FORMULA

From Mohammad K. Azarian, Dec 27 2008: (Start)

G.f.: 1/(1-2*x)+1/(1-5*x)+1/(1-7*x).

E.g.f.: exp(2*x)+exp(5*x)+exp(7*x). (End)

a(n) = 14*a(n-1) - 59*a(n-2) + 70*a(n-3) for n > 2. - Wesley Ivan Hurt, Oct 06 2017

MAPLE

A074538:=n->2^n+5^n+7^n: seq(A074538(n), n=0..30); # Wesley Ivan Hurt, Oct 06 2017

MATHEMATICA

Table[2^n + 5^n + 7^n, {n, 0, 20}]

LinearRecurrence[{14, -59, 70}, {3, 14, 78}, 20] (* Harvey P. Dale, Dec 21 2016 *)

PROG

(MAGMA) [2^n + 5^n + 7^n: n in [0..25]]; // Vincenzo Librandi, Jun 11 2011

CROSSREFS

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

Sequence in context: A330518 A228656 A244507 * A242426 A001564 A277132

Adjacent sequences:  A074535 A074536 A074537 * A074539 A074540 A074541

KEYWORD

easy,nonn

AUTHOR

Robert G. Wilson v, Aug 23 2002

STATUS

approved

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Last modified March 29 02:19 EDT 2020. Contains 333104 sequences. (Running on oeis4.)