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%I #16 Sep 03 2019 03:07:08
%S 0,0,1,0,0,3,0,0,2,0,0,12,0,0,4,0,0,12,0,0,4,0,0,60,0,0,8,0,0,48,0,0,
%T 4,0,0,128,0,0,4,0,0,48,0,0,16,0,0,288,0,0,4,0,0,96,0,0,16,0,0,768,0,
%U 0,16,0,0,48,0,0,16,0,0,1280,0,0,24,0,0,96,0
%N Number of even divisors of Fibonacci(n).
%H Amiram Eldar, <a href="/A193291/b193291.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A183063(A000045(n)). - _Amiram Eldar_, Sep 03 2019
%e a(6) = 3 because Fibonacci(6) = 8 and the 3 even divisors are {2, 4, 8}.
%t a[n_] := Block[{d = Divisors[Fibonacci[n]]}, Count[EvenQ[d], True]]; Table[a[n], {n, 110}]
%o (PARI) a(n)=if(n%3,0,numdiv(fibonacci(n)/2)) \\ _Charles R Greathouse IV_, Jul 30 2011
%Y Cf. A000045, A183063.
%K nonn
%O 1,6
%A _Michel Lagneau_, Jul 21 2011