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The American Mathematical Monthly
The American Mathematical Monthly is a journal in which university researchers post problems and challenge us to solve them. I am citing here some problems that I solved during my studies.

April 2018
Problem 11933 [PDF]
Problem 11932 [PDF]
Gerald A. Edgar, Daniel H. Ullman & Douglas B. West (2018)
Problems and Solutions, The American Mathematical Monthly, 125:5, 466475
DOI: 10.1080/00029890.2018.1447207 
September 2016
Problem 11918 [PDF]
Gerald A. Edgar, Daniel H. Ullman & Douglas B. West (2018)
Problems and Solutions, The American Mathematical Monthly, 125:3, 276283
DOI: 10.1080/00029890.2018.1424478 
March 2016
Problem 11884 [PDF]
Gerald A. Edgar, Daniel H. Ullman & Douglas B. West (2017)
(2017) Problems and Solutions, The American Mathematical Monthly, 124:10, 970978
DOI: 10.4169/amer.math.monthly.124.10.970
Memopi
I created the Memopi game which consists of typing as many decimal places as possible of the number pi to increase the score.
Best score: 613902 with 510 decimal places, well done DR!