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 A171410 #7 Dec 15 2017 17:37:10 %S A171410 7,151,10501,1005001,100050001,10000500001,1000005000001, %T A171410 100000050000001,10000000500000001,1000000005000000001, %U A171410 100000000050000000001,10000000000500000000001 %N A171410 1+5*10^n+100^n. %H A171410 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (111,-1110,1000) %F A171410 From _Chai Wah Wu_, May 30 2016: (Start) %F A171410 a(n) = 111*a(n-1) - 1110*a(n-2) + 1000*a(n-3) for n > 2. %F A171410 G.f.: (1510*x^2 - 626*x + 7)/((1 - x)*(1 - 10*x)*(1 - 100*x)). (End) %F A171410 E.g.f.: (1 + 5*exp(9*x) + exp(99*x))*exp(x). - _Ilya Gutkovskiy_, May 30 2016 %K A171410 easy,nonn %O A171410 0,1 %A A171410 _Jason Earls_, Dec 08 2009