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 A081596 #16 Feb 26 2025 10:57:20
%S A081596 0,1,2,3,4,5,6,7,8,9,5,6,7,8,9,10,11,12,13,14,10,11,12,13,14,15,16,17,
%T A081596 18,19,15,16,17,18,19,20,21,22,23,24,20,21,22,23,24,25,26,27,28,29,25,
%U A081596 26,27,28,29,30,31,32,33,34,30,31,32,33,34,35,36,37,38,39,35,36,37,38,39,40,41
%N A081596 Let n = 10x + y where 0 <= y <= 9, x >= 0. Then a(n) = 5x+y.
%H A081596 Vincenzo Librandi, <a href="/A081596/b081596.txt">Table of n, a(n) for n = 0..2000</a>
%H A081596 <a href="/index/Rec#order_11">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,0,0,0,0,0,1,-1).
%F A081596 G.f.: -x*(4*x^9 -x^8 -x^7 -x^6 -x^5 -x^4 -x^3 -x^2 -x -1) / ((x -1)^2*(x +1)*(x^4 -x^3 +x^2 -x +1)*(x^4 +x^3 +x^2 +x +1)). - _Colin Barker_, Jun 24 2014
%F A081596 a(n) = n - 5*floor(n/10). [_Bruno Berselli_, Jun 24 2014]
%t A081596 CoefficientList[Series[-x (4 x^9 - x^8 - x^7 - x^6 - x^5 - x^4 - x^3 - x^2 - x - 1)/((x - 1)^2 (x + 1) (x^4 - x^3 + x^2 - x + 1) (x^4 + x^3 + x^2 + x + 1)), {x, 0, 150}], x] (* _Vincenzo Librandi_, Jun 25 2014 *)
%o A081596 (PARI) my(n, x, y); vector(200, n, y=(n-1)%10; x=(n-1-y)\10; 5*x+y) \\ _Colin Barker_, Jun 24 2014
%o A081596 (Magma) k:=5; [n-(10-k)*Floor(n/10): n in [0..100]]; // _Bruno Berselli_, Jun 24 2014
%Y A081596 Cf. A081502. Different from A028900.
%K A081596 nonn
%O A081596 0,3
%A A081596 _N. J. A. Sloane_, Apr 22 2003