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 A070346 #19 Dec 18 2023 14:26:23
%S A070346 1,3,9,27,7,21,26,4,12,36,34,28,10,30,16,11,33,25,1,3,9,27,7,21,26,4,
%T A070346 12,36,34,28,10,30,16,11,33,25,1,3,9,27,7,21,26,4,12,36,34,28,10,30,
%U A070346 16,11,33,25,1,3,9,27,7,21,26,4,12,36,34,28,10,30,16,11
%N A070346 a(n) = 3^n mod 37.
%H A070346 G. C. Greubel, <a href="/A070346/b070346.txt">Table of n, a(n) for n = 0..1000</a>
%H A070346 <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (1, 0, 0, 0, 0, 0, 0, 0, -1, 1).
%F A070346 a(n) = a(n-18). - _G. C. Greubel_, Mar 11 2016
%t A070346 Table[PowerMod[3,n,37],{n,0,70}] (* _Harvey P. Dale_, Jan 19 2011 *)
%o A070346 (PARI) a(n)=lift(Mod(3,37)^n) \\ _Charles R Greathouse IV_, Mar 22 2016
%K A070346 nonn,easy
%O A070346 0,2
%A A070346 _N. J. A. Sloane_, May 12 2002