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 A147840 #15 Jan 03 2024 08:44:59
%S A147840 1,8,72,656,5984,54592,498048,4543744,41453056,378180608,3450181632,
%T A147840 31476371456,287162261504,2619811643392,23900818341888,
%U A147840 218049690271744,1989290355982336,18148506037649408,165570737528635392
%N A147840 a(n)=10*a(n-1)-8*a(n-2), a(0)=1, a(1)=8 .
%C A147840 a(n) = sum_{k=0..n} 2^n*binomial(n,k)*A007482(k) = 2^n*A052913(n). - _R. J. Mathar_, Oct 15 2012
%H A147840 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (10,-8).
%F A147840 a(n)=Sum_{k, 0<=k<=n}A147703(n,k)*7^k . G.f.: (1-2x)/(1-10x+8*x^2).
%F A147840 a(n)= ((17+3*sqrt(17))/34)*(5+sqrt(17))^n + ((17-3*sqrt(17))/34)*(5-sqrt(17))^n [From _Richard Choulet_, Nov 20 2008]
%F A147840 G.f.: (1-2x)/(1-10x+8x^2). - _Harvey P. Dale_, Dec 02 2021
%t A147840 LinearRecurrence[{10,-8},{1,8},20] (* _Harvey P. Dale_, Dec 02 2021 *)
%K A147840 nonn,easy
%O A147840 0,2
%A A147840 _Philippe Deléham_, Nov 14 2008