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3^a(n) is the highest power of 3 dividing A214551(n).
3

%I #19 Sep 08 2022 08:46:05

%S 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 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 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 3^a(n) is the highest power of 3 dividing A214551(n).

%C This is the 3-adic valuation of A214551.

%H Reinhard Zumkeller, <a href="/A227837/b227837.txt">Table of n, a(n) for n = 0..10000</a>

%t f[l_List] := Append[l, (l[[-1]] + l[[-3]])/GCD[l[[-1]], l[[-3]]]];

%t A214551[m_] := Nest[f, {1, 1, 1}, m]; IntegerExponent[A214551[200], 3] (* _G. C. Greubel_, Apr 28 2017 *)

%o (Haskell)

%o a227837 = a007949 . a214551 -- _Reinhard Zumkeller_, Aug 05 2013

%o (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 Cf. A000930, A007949, A214551, A227835, A227836.

%K nonn

%O 0,14

%A _N. J. A. Sloane_, Aug 04 2013