A115043 - OEIS

%I #4 Mar 30 2012 18:40:02

%S 3,5,15,3,45,15,675,45,30375,675,20503125,30375,622782421875,20503125,

%T 12768985843505859375,622782421875,7952299928506168842315673828125,

%U 12768985843505859375

%N a(0)=3, a(1)=5. a(n) = a(n-1)*a(n-2) if n odd, else a(n) = a(n-1)/a(n-2).

%C All divisors >1 of the terms are also in the sequence.

%F a(n) = a(n-2)*a(n-4) if n odd. a(n)=a(n-3) if n even.

%F a(2n+1) = 3^Fibonacci(n+1) * 5^Fibonacci(n).

%F a(2n) = 3^Fibonacci(n-1) * 5^Fibonacci(n-2).

%Y Cf. A115033, A115034, A174348.

%K easy,nonn

%O 0,1

%A _Giovanni Teofilatto_, Feb 28 2006

%E Formulas corrected by _R. J. Mathar_, Mar 16 2010