We introduce the function a(r, n) which counts tilings of length n + r that utilize white tiles (whose lengths can vary between 1 and n) and r identical red squares. These tilings are called two-toned tilings. We provide combinatorial proofs of several identities satisfied by a(r, n) and its generalizations, including one that produces kth order Fibonacci numbers. Applications to integer partitions are also provided.
© 2011 Fibonacci Association
Benjamin, Arthur T., Phyllis Chinn, Jacob N. Scott and Greg Simay. "Combinatorics of Two Toned Tilings." The Fibonacci Quarterly, Vol. 49, No. 4, pp. 290-297, November 2011.