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 A024101 #35 Jul 08 2025 17:27:43 %S A024101 0,8,80,728,6560,59048,531440,4782968,43046720,387420488,3486784400, %T A024101 31381059608,282429536480,2541865828328,22876792454960, %U A024101 205891132094648,1853020188851840,16677181699666568,150094635296999120 %N A024101 a(n) = 9^n-1. %C A024101 Number of integers from 0 to 10^(n+1)-1 that lack any particular digit other than 0. - _Robert G. Wilson v_, Apr 14 2003 %C A024101 These are the numbers 888...8 in base 9. - _Zerinvary Lajos_, Nov 21 2007 %H A024101 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (10,-9). %F A024101 G.f.: 1/(1-9*x)-1/(1-x). - _Mohammad K. Azarian_, Jan 14 2009 %F A024101 E.g.f.: e^(9*x)-e^x. - _Mohammad K. Azarian_, Jan 14 2009 %F A024101 a(n) = A024023(n)*A034472(n). - _Reinhard Zumkeller_, Feb 14 2009 %F A024101 a(n) = 9*a(n-1)+8 for n>0, a(0)=0. - _Vincenzo Librandi_, Nov 19 2010 %F A024101 a(0)=0, a(1)=8; for n>1, a(n) = 10*a(n-1)-9*a(n-2). - _Harvey P. Dale_, Apr 14 2015 %F A024101 a(n) = Sum_{i=1..n} 8^i*binomial(n,n-i) for n>0, a(0)=0. - _Bruno Berselli_, Nov 11 2015 %F A024101 a(n) = A001019(n) - 1. - _Sean A. Irvine_, Jun 19 2019 %F A024101 Sum_{n>=1} 1/a(n) = A248726. - _Amiram Eldar_, Nov 13 2020 %t A024101 Table[9^n - 1, {n, 0, 20}] %t A024101 LinearRecurrence[{10, -9}, {0, 8}, 30] (* _Harvey P. Dale_, Apr 14 2015 *) %o A024101 (PARI) a(n)=9^n-1 \\ _Charles R Greathouse IV_, Jun 11 2015 %Y A024101 Cf. A001019, A024023, A034472, A052386, A052379, A248726. %K A024101 nonn,easy %O A024101 0,2 %A A024101 _N. J. A. Sloane_