期刊: AMERICAN MATHEMATICAL MONTHLY, 2021; 128 (6)
It is a 300-year-old counterintuitive observation of Prince Rupert of the Rhine that in the cube a straight tunnel can be cut through which a second c......
期刊: AMERICAN MATHEMATICAL MONTHLY, 2021; 128 (2)
In this note, we show that each positive rational number can be written uniquely as phi(m(2))/phi(n(2)), where m, n is an element of N, with some natu......
期刊: AMERICAN MATHEMATICAL MONTHLY, 2020; 127 (6)
We show how the determinant of a matrix can be calculated using complex analysis of one variable. We also describe the connection between unitary matr......
期刊: AMERICAN MATHEMATICAL MONTHLY, 2020; 128 (1)
In this note, we prove a graph inequality based on the sizes of the common neighborhoods. We also characterize the extremal graphs that achieve equali......
期刊: AMERICAN MATHEMATICAL MONTHLY, 2020; 127 (9)
In this note, we show that each positive rational number can be written as phi(m(2))/phi(n(2)), where phi is Euler's totient function andmandnare posi......
期刊: AMERICAN MATHEMATICAL MONTHLY, 2020; 127 (9)
Do examples as in the title exist? It depends on how the termRiemann sumis understood. For the standard, left, or right Riemann sums such examples do ......
期刊: AMERICAN MATHEMATICAL MONTHLY, 2020; 127 (1)
Let G be an electrical network graph with vertex set V and edge set E, and let be the effective resistance between vertices i and j of G. Foster's fir......
期刊: AMERICAN MATHEMATICAL MONTHLY, 2020; 127 (2)
A probabilistic proof of a recursion formula for sums of powers is given by using some properties of expectations.
期刊: AMERICAN MATHEMATICAL MONTHLY, 2020; 127 (10)
The Smarandache function of a positive integer n, denoted by S(n), is defined to be the smallest positive integer j such that n divides the factorial ......
期刊: AMERICAN MATHEMATICAL MONTHLY, 2020; 127 (10)
A decomposition of an integer n as a sum of several fractions is called faithful if no positive integer less than n can be obtained by replacing some ......
期刊: AMERICAN MATHEMATICAL MONTHLY, 2020; 127 (3)
Benford's law is an empirical "law" governing the frequency of leading digits in numerical data sets. Surprisingly, for mathematical sequences the pre......