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 A155643 #14 Jun 12 2015 15:26:54
%S A155643 1,6,76,876,9376,96876,984376,9921876,99609376,998046876,9990234376,
%T A155643 99951171876,999755859376,9998779296876,99993896484376,
%U A155643 999969482421876,9999847412109376,99999237060546876,999996185302734376
%N A155643 10^n-5^n+1.
%H A155643 <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (16,-65,50).
%F A155643 G.f.: 1/(1-10*x)-1/(1-5*x)+1/(1-x). E.g.f.: e^(10*x)-e^(5*x)+e^x.
%F A155643 a(n)=15*a(n-1)-50*a(n-2)+36 with a(0)=1, a(1)=6 - _Vincenzo Librandi_, Jul 21 2010
%t A155643 Table[10^n-5^n+1,{n,0,20}] (* _Harvey P. Dale_, Oct 02 2011 *)
%o A155643 (PARI) a(n)=10^n-5^n+1^n \\ _Charles R Greathouse IV_, Jun 11 2015
%Y A155643 Cf. A155628, A155629, A155630, A155631, A155632, A155633, A155634, A155635, A155636, A155637, A155638, A155639, A155640, A155641, A155642.
%K A155643 nonn,easy
%O A155643 0,2
%A A155643 _Mohammad K. Azarian_, Jan 30 2009