OFFSET
1,2
COMMENTS
5 divides a(4k). a(1) = 1 and a(4k+2) = 1 for k>0.
FORMULA
a(n) = Numerator[Sum[Lucas[k],{k,1,n}]/Product[Lucas[k],{k,1,n}]], where Lucas[k] = Fibonacci[k-1] + Fibonacci[k+1].
MATHEMATICA
Table[Numerator[Sum[Fibonacci[k-1]+Fibonacci[k+1], {k, 1, n}]/Product[Fibonacci[k-1]+Fibonacci[k+1], {k, 1, n}]], {n, 1, 100}]
CROSSREFS
KEYWORD
frac,nonn
AUTHOR
Alexander Adamchuk, Aug 16 2006
STATUS
approved