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A074577 a(n) = 6^n + 7^n + 8^n. 1

%I

%S 3,21,149,1071,7793,57351,426449,3200631,24221633,184649031,

%T 1416683249,10930058391,84737546273,659705518311,5154633748049,

%U 40402118583351,317529017187713,2501356987117191,19744372064060849,156123443001239511

%N a(n) = 6^n + 7^n + 8^n.

%H Vincenzo Librandi, <a href="/A074577/b074577.txt">Table of n, a(n) for n = 0..300</a>

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (21,-146,336).

%F From _Mohammad K. Azarian_, Dec 30 2008: (Start)

%F G.f.: 1/(1-6*x) + 1/(1-7*x) + 1/(1-8*x).

%F E.g.f.: e^(6*x) + e^(7*x) + e^(8*x). (End)

%F a(n) = 21*a(n-1) - 146*a(n-2) + 336*a(n-3); a(0)=3, a(1)=21, a(2)=149. - _Harvey P. Dale_, Dec 25 2011

%t Table[6^n + 7^n + 8^n, {n, 0, 19}]

%t LinearRecurrence[{21,-146,336},{3,21,149},20] (* _Harvey P. Dale_, Dec 25 2011 *)

%o (MAGMA) [6^n + 7^n + 8^n: n in [0..20]]; // _Vincenzo Librandi_, May 20 2011

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

%K easy,nonn

%O 0,1

%A _Robert G. Wilson v_, Aug 23 2002

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Last modified February 17 23:35 EST 2020. Contains 332006 sequences. (Running on oeis4.)