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 A078412 #12 Mar 13 2024 08:30:57
%S A078412 5,8,13,7,20,1,7,8,5,13,2,5,7,4,11,5,16,7,23,10,11,7,2,1,1,2,1,1,2,1,
%T A078412 1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,
%U A078412 2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2,1,1,2
%N A078412 a(0) = 5, a(1) = 8; for n >1, a(n)=(a(n-1)+a(n-2))/3^n, where 3^n is the highest power of 3 dividing a(n-1)+a(n-2).
%H A078412 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,1).
%F A078412 a(3n-1)=2, a(3n)=1, a(3n+1)=1 for n>=8. - _Sascha Kurz_, Jan 04 2003
%t A078412 Join[{5, 8, 13, 7, 20, 1, 7, 8, 5, 13, 2, 5, 7, 4, 11, 5, 16, 7, 23, 10, 11, 7},LinearRecurrence[{0, 0, 1},{2, 1, 1},79]] (* _Ray Chandler_, Aug 25 2015 *)
%Y A078412 Cf. A038502, A078414.
%K A078412 nonn,easy
%O A078412 0,1
%A A078412 _Yasutoshi Kohmoto_, Dec 28 2002
%E A078412 More terms from _Sascha Kurz_, Jan 04 2003