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%I #10 Apr 08 2016 03:10:06
%S 1,-7,-63,-455,-3199,-22407,-156863,-1098055,-7686399,-53804807,
%T -376633663,-2636435655,-18455049599,-129185347207,-904297430463,
%U -6330082013255,-44310574092799,-310174018649607,-2171218130547263,-15198526913830855,-106389688396815999
%N a(n) = (7-4*7^n)/3.
%H G. C. Greubel, <a href="/A165759/b165759.txt">Table of n, a(n) for n = 0..500</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (8, -7).
%F a(n) = 7*a(n-1)-14, a(0)=1.
%F a(n) = 8*a(n-1) - 7*a(n-2), a(0)= 1, a(1)= -7, for n>1.
%F G.f.: (1-15x)/(1-8x+7x^2).
%F a(n) = Sum_{0<=k<=n} A112555(n,k)*(-8)^(n-k).
%F E.g.f.: (1/3)*(7*exp(x) - 4*exp(7*x)). - _G. C. Greubel_, Apr 07 2016
%t (7-4*7^Range[0,20])/3 (* or *) LinearRecurrence[{8,-7},{1,-7},30] (* _Harvey P. Dale_, Dec 21 2014 *)
%K easy,sign
%O 0,2
%A _Philippe Deléham_, Sep 26 2009
%E Corrected and extended by _Harvey P. Dale_, Dec 21 2014