%I A055845
%S A055845 1,8,31,116,433,1616,6031,22508,84001,313496,1169983,4366436,16295761,
%T A055845 60816608,226970671,847066076,3161293633,11798108456,44031140191,
%U A055845 164326452308,613274669041,2288772223856
%N A055845 a(n)=4a(n-1)-a(n-2); a(0)=1, a(1)=8.
%D A055845 A. H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, 
               pps. 194-196.
%H A055845 <a href="Sindx_Rea.html#recLCC">Index entries for sequences related to 
               linear recurrences with constant coefficients</a>
%H A055845 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/
               RecursiveSequences.html">Recursive Sequences</a>
%F A055845 a(n)={8*[(2+sqrt(3))^n-(2-sqrt(3))^n]-[(2+sqrt(3))^(n-1) -(2-sqrt(3))^(n-1)]}/
               2*sqrt(3).
%e A055845 G.f.(x)=(1+4x)/(1-4x+x^2).
%Y A055845 Cf. A054485.
%Y A055845 Sequence in context: A115004 A005338 A006322 this_sequence A034556 A121097 
               A121093
%Y A055845 Adjacent sequences: A055842 A055843 A055844 this_sequence A055846 A055847 
               A055848
%K A055845 easy,nonn
%O A055845 0,2
%A A055845 Barry E. Williams, May 31 2000