By Zehava YACHAS
(Exclusively published in the Personal Journal of Shalosh B. Ekhad and Doron Zeilberger)
Written: Nov. 21, 2011.
In 1975, high-school student Jeffrey Shallit published a simple proof that the Golden Ratio, φ, is irrational. The present proof is yet simpler, since it does not use divisibility, only additivity.
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