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 A155158 #26 Feb 25 2024 05:59:02
%S A155158 1,5,7,3,1,5,7,3,1,5,7,3,1,5,7,3,1,5,7,3,1,5,7,3,1,5,7,3,1,5,7,3,1,5,
%T A155158 7,3,1,5,7,3,1,5,7,3,1,5,7,3,1,5,7,3,1,5,7,3,1,5,7,3,1,5,7,3,1,5,7,3,
%U A155158 1,5,7,3,1,5,7,3,1,5,7,3,1,5,7,3,1,5
%N A155158 Period 4: repeat [1, 5, 7, 3].
%H A155158 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (1,-1,1).
%F A155158 a(n) = A048473(n) mod 10.
%F A155158 First differences: a(n+1)-a(n) = (-1)^floor(n/2)*A010694(n+1).
%F A155158 Second differences: a(n+2)-2*a(n+1)+a(n) = (-1)^floor(1+n/2)*A010696(n).
%F A155158 Third differences: a(n+3)-3*a(n+2)+3*a(n+1)-a(n) = (-1)^floor((n+3)/2)*A105398(n).
%F A155158 G.f.: (1+4*x+3*x^2)/(1-x+x^2-x^3). - _Colin Barker_, Feb 28 2012
%F A155158 a(n) = a(n-1) - a(n-2) + a(n-3) for n>2. - _Wesley Ivan Hurt_, Jul 08 2016
%p A155158 seq(op([1, 5, 7, 3]), n=0..50); # _Wesley Ivan Hurt_, Jul 08 2016
%t A155158 PadRight[{}, 300, {1, 5, 7, 3}] (* _Wesley Ivan Hurt_, Jul 08 2016 *)
%o A155158 (Magma) &cat [[1, 5, 7, 3]^^30]; // _Wesley Ivan Hurt_, Jul 08 2016
%Y A155158 Cf. A010694, A010696, A048473, A105398.
%K A155158 nonn,easy
%O A155158 0,2
%A A155158 _Paul Curtz_, Jan 21 2009