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 A227837 #19 Sep 08 2022 08:46:05
%S A227837 0,0,0,0,1,0,1,0,1,0,0,0,0,2,0,1,0,2,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,0,
%T A227837 1,0,3,0,0,0,2,0,0,0,0,2,0,2,1,0,0,0,0,1,0,1,0,1,3,0,0,0,1,0,1,1,0,0,
%U A227837 0,1,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,1,0,5,0,0,0
%N A227837 3^a(n) is the highest power of 3 dividing A214551(n).
%C A227837 This is the 3-adic valuation of A214551.
%H A227837 Reinhard Zumkeller, <a href="/A227837/b227837.txt">Table of n, a(n) for n = 0..10000</a>
%t A227837 f[l_List] := Append[l, (l[[-1]] + l[[-3]])/GCD[l[[-1]], l[[-3]]]];
%t A227837 A214551[m_] := Nest[f, {1, 1, 1}, m]; IntegerExponent[A214551[200], 3] (* _G. C. Greubel_, Apr 28 2017 *)
%o A227837 (Haskell)
%o A227837 a227837 = a007949 . a214551 -- _Reinhard Zumkeller_, Aug 05 2013
%o A227837 (Magma) m:=100; A214551:=[i le 2 select 1 else (Self(i)+Self(i-2)) div Gcd(Self(i),Self(i-2)): i in [0..m]]; [Valuation(A214551[n],3): n in [1..m+1]]; // _Bruno Berselli_, Aug 05 2013
%Y A227837 Cf. A000930, A007949, A214551, A227835, A227836.
%K A227837 nonn
%O A227837 0,14
%A A227837 _N. J. A. Sloane_, Aug 04 2013