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 A086944 #21 Apr 30 2025 16:23:31 %S A086944 42,492,4992,49992,499992,4999992,49999992,499999992,4999999992, %T A086944 49999999992,499999999992,4999999999992,49999999999992, %U A086944 499999999999992,4999999999999992,49999999999999992,499999999999999992,4999999999999999992,49999999999999999992,499999999999999999992 %N A086944 a(n) = k where R(k+8) = 5. %H A086944 Vincenzo Librandi, <a href="/A086944/b086944.txt">Table of n, a(n) for n = 1..300</a> %H A086944 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (11,-10). %F A086944 a(n) = 5*10^n - 8. %F A086944 R(a(n)) = A086941(n). %F A086944 From _Elmo R. Oliveira_, Apr 30 2025: (Start) %F A086944 G.f.: 6*x*(5*x+7)/((x-1)*(10*x-1)). %F A086944 E.g.f.: 3 - 8*exp(x) + 5*exp(10*x). %F A086944 a(n) = 11*a(n-1) - 10*a(n-2) for n > 2. (End) %o A086944 (Magma) [5*10^n-8: n in [1..25] ]; // _Vincenzo Librandi_, Aug 22 2011 %Y A086944 Cf. A004086, A086941. %K A086944 nonn,base,easy %O A086944 1,1 %A A086944 _Ray Chandler_, Jul 24 2003