# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/
Search: id:a164603
Showing 1-1 of 1
%I A164603 #20 Sep 08 2022 08:45:47
%S A164603 1,18,76,376,1808,8736,42176,203648,983296,4747776,22924288,110688256,
%T A164603 534450176,2580553728,12460015616,60162277376,290489171968,
%U A164603 1402605797376,6772379877376,32699942699008,157889290305536
%N A164603 a(n) = ((1+4*sqrt(2))*(2+2*sqrt(2))^n + (1-4*sqrt(2))*(2-2*sqrt(2))^n)/2.
%C A164603 Binomial transform of A164602. Second binomial transform of A164702. Inverse binomial transform of A164604.
%H A164603 G. C. Greubel, Table of n, a(n) for n = 0..1000 (terms 0..164 from Vincenzo Librandi)
%H A164603 Index entries for linear recurrences with constant coefficients, signature (4,4).
%F A164603 a(n) = 4*a(n-1) + 4*a(n-2) for n > 1; a(0) = 1, a(1) = 18.
%F A164603 G.f.: (1+14*x)/(1-4*x-4*x^2).
%F A164603 E.g.f.: exp(2*x)*( cosh(2*sqrt(2)*x) + 4*sqrt(2)*sinh(2*sqrt(2)*x) ). - _G. C. Greubel_, Aug 11 2017
%t A164603 CoefficientList[Series[(-1-14 n)/(-1+4 n+4 n^2),{n,0,20}],n] (* _Harvey P. Dale_, Feb 22, 2011 *)
%o A164603 (Magma) Z