A Bijective Proof of Richard Stanley's Observation that the sum of the cubes of the n-th row of`
Stern's Diatomic array equals 3 times 7n-1
By Shalosh B. Ekhad and Doron Zeilberger
Written: March 3, 2021
Exclusively published in the Personal Journal of Shalosh B. Ekhad and Doron Zeilberger
In a delightful article, Richard Stanley derived, algebraically, the surprisingly simple
formula, 3*7n-1, for the sum of the cubes of the n-th row of Stern's diatomic array.
In this note, we find an elegant bijective proof of this surprising fact, that
explains it and gives insight. The novelty is that
this gorgeous bijection was discovered by a computer (SBE), with minimal guidance by a human (DZ).
This debunks the conventional wisdom, held by some human supremacists, that computers
can only compute, but they can't give insight.
a Maple package that discoveres and implements the bijection of the paper
Sample Input and Output Files for BijectionStern.txt
If you want to see how the bijection acts for all balanced 3 by n matrices for n from 1 to 5,
The input file gives you
the output file .
Personal Journal of SBE and DZ
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