Published in volume 42.1, February 2004 issue of The Fibonacci Quarterly (Submitted July 2001 - Third revision June 2002).
Abstract
Inspired by Denton Hewgill's identity:
where
we prove an analogous identity involving the Fibonacci number system:
which holds for all integers n >= 0, d >= 0,
where En+d stands for Fn+d
(the n+d:th Fibonacci number) if n is even,
and Ln+d (the n+d:th Lucas number)
if n is odd.