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 A165755 #13 Apr 08 2016 03:10:16
%S A165755 1,-5,-35,-185,-935,-4685,-23435,-117185,-585935,-2929685,-14648435,
%T A165755 -73242185,-366210935,-1831054685,-9155273435,-45776367185,
%U A165755 -228881835935,-1144409179685,-5722045898435,-28610229492185
%N A165755 a(n) = (5-3*5^n)/2.
%H A165755 G. C. Greubel, <a href="/A165755/b165755.txt">Table of n, a(n) for n = 0..500</a>
%H A165755 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (6, -5).
%F A165755 a(n) = 5*a(n-1) - 10, a(0)=1.
%F A165755 a(n) = 6*a(n-1)-5*a(n-2), a(0)= 1, a(1)= -5, for n>1.
%F A165755 G.f.: (1-11x)/(1-6x+5x^2).
%F A165755 a(n) = Sum_{0<=k<=n} A112555(n,k)*(-6)^(n-k).
%F A165755 a(n) = (-5)*A057651(n-1).
%F A165755 E.g.f.: (1/2)*(5*exp(x) - 3*exp(5*x)). - _G. C. Greubel_, Apr 07 2016
%t A165755 (5-3*5^Range[0,20])/2 (* or *) LinearRecurrence[{6,-5},{1,-5},20] (* _Harvey P. Dale_, Apr 18 2013 *)
%o A165755 (PARI) x='x+O('x^99); Vec((1-11*x)/(1-6*x+5*x^2)) \\ _Altug Alkan_, Apr 07 2016
%K A165755 easy,sign
%O A165755 0,2
%A A165755 _Philippe Deléham_, Sep 26 2009