This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A163071 #16 Sep 08 2022 08:45:46
%S A163071 4,17,86,448,2344,12272,64256,336448,1761664,9224192,48298496,
%T A163071 252894208,1324171264,6933450752,36304019456,190090313728,
%U A163071 995325804544,5211593572352,27288258215936,142883175006208,748146017173504
%N A163071 a(n) = ((4+sqrt(5))*(3+sqrt(5))^n + (4-sqrt(5))*(3-sqrt(5))^n)/2.
%C A163071 Binomial transform of A163070. Third binomial transform of A163141. Inverse binomial transform of A108404 without initial 1.
%H A163071 Harvey P. Dale, <a href="/A163071/b163071.txt">Table of n, a(n) for n = 0..1000</a>
%H A163071 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (6, -4).
%F A163071 a(n) = 6*a(n-1) - 4*a(n-2) for n > 1; a(0) = 4, a(1) = 17.
%F A163071 G.f.: (4-7*x)/(1-6*x+4*x^2).
%F A163071 a(n) = 2^(n+1) * A000032(2*n) + 5 * 2^(n-1) * A000045(2*n) = 2^(n+1) * A005248(n) + 5 * 2^(n-1) * A001906(n). - _Diego Rattaggi_, Aug 02 2020
%t A163071 LinearRecurrence[{6,-4},{4,17},40] (* _Harvey P. Dale_, Feb 12 2013 *)
%o A163071 (Magma) Z<x>:=PolynomialRing(Integers()); N<r>:=NumberField(x^2-5); S:=[ ((4+r)*(3+r)^n+(4-r)*(3-r)^n)/2: n in [0..20] ]; [ Integers()!S[j]: j in [1..#S] ]; // _Klaus Brockhaus_, Jul 21 2009
%Y A163071 Cf. A163070, A163141, A108404.
%K A163071 nonn
%O A163071 0,1
%A A163071 Al Hakanson (hawkuu(AT)gmail.com), Jul 20 2009
%E A163071 Edited and extended beyond a(5) by _Klaus Brockhaus_, Jul 21 2009