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A227836
2^a(n) is the highest power of 2 dividing A214551(n).
3
0, 0, 0, 1, 0, 2, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 2, 0, 2, 1, 0, 0, 0, 2, 0, 2, 1, 0, 0, 0, 4, 0, 3, 0, 1, 0, 3, 0, 2, 0, 2, 1, 0, 0, 0, 2, 0, 2, 1, 0, 0, 0, 4, 0, 3, 0, 2, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 1, 3, 0, 0, 0, 6, 0, 1, 0, 1, 3, 0, 0, 0, 3, 0, 1, 0, 1, 5, 0, 0, 0, 3, 0, 2, 0
OFFSET
0,6
COMMENTS
This is the 2-adic valuation of A214551.
LINKS
MATHEMATICA
f[l_List] := Append[l, (l[[-1]] + l[[-3]])/GCD[l[[-1]], l[[-3]]]];
A214551[m_] := Nest[f, {1, 1, 1}, m]; IntegerExponent[A214551[200], 2] (* G. C. Greubel, Apr 28 2017 *)
PROG
(Haskell)
a227836 = a007814 . a214551 -- Reinhard Zumkeller, Aug 05 2013
(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], 2): n in [1..m+1]]; // Bruno Berselli, Aug 05 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Aug 04 2013
STATUS
approved