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 A057933 #6 Apr 03 2025 10:21:29 %S A057933 9,98,987,9876,98765,987654,9876543,98765432,987654320,9876543209, %T A057933 98765432098,987654320987,9876543209876,98765432098765, %U A057933 987654320987654,9876543209876543,98765432098765432,987654320987654320 %N A057933 Floor[(80/81)*10^n]. %H A057933 <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (10,0,0,0,0,0,0,0,1,-10). %F A057933 G.f.:(9x+8x^2+7x^3+6x^4+5x^5+4x^6+3x^7+2x^8)/((1-10x)(1-x^9)). %F A057933 a(n)=10*a(n-1)-(n%9)+10*(n%9!=0). %t A057933 Floor[80/81*10^Range[20]] (* _Harvey P. Dale_, May 28 2017 *) %o A057933 (PARI) a(n)=10^n*80\81 %Y A057933 Cf. A057932. %K A057933 nonn %O A057933 1,1 %A A057933 _Henry Bottomley_, Oct 04 2000