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 A155615 #15 Jul 11 2023 15:20:52 %S A155615 1,8,92,974,9920,99758,999272,9997814,99993440,999980318,9999940952, %T A155615 99999822854,999999468560,9999998405678,99999995217032, %U A155615 999999985651094,9999999956953280,99999999870859838,999999999612579512 %N A155615 a(n) = 10^n - 3^n + 1. %H A155615 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (14,-43,30). %F A155615 G.f.: 1/(1-10*x)-1/(1-3*x)+1/(1-x). %F A155615 E.g.f.: e^(10*x)-e^(3*x)+e^x. %F A155615 a(n) = 13*a(n-1)-30*a(n-2)+18 with a(0)=1, a(1)=8. - _Vincenzo Librandi_, Jul 21 2010 %o A155615 (PARI) a(n)=10^n-3^n+1 \\ _Charles R Greathouse IV_, Oct 07 2015 %Y A155615 Cf. A155599, A155600, A155601, A155602, A155603, A155604, A155605, A155606, A155607, A155608, A155609, A155610, A155611, A155612, A155613, A155614. %K A155615 nonn,easy %O A155615 0,2 %A A155615 _Mohammad K. Azarian_, Jan 26 2009