A Bijection between Two Classes of Restricted Compositions
Two proofs, one using generating functions, the other bijective, are given for the following theorem: The number of compositions of n into parts congruent to 1 (mod k) equals the number of compositions of n + k − 1 into parts greater than k − 1. This bijection is then proven to hold for palindromic compositions. A more general theorem is presented in conclusion.
Diffenderfer, James D..
"A Bijection between Two Classes of Restricted Compositions."
Fibonacci Quarter, 50 (4): 360-365.