筛选条件 共查询到30条结果
排序方式
Cubes and Boxes Have Rupert's Passages in Every Nontrivial Direction

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......

Positive Rational Numbers of the Form phi(m(2))/phi(n(2))

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......

Finding the Determinant of a Matrix via Complex Analysis

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......

Foster, Turan, and Neighbors

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......

Each Positive Rational Number Has the Form phi(m(2))/phi(n(2))

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......

Distinct Continuous Maps with All Riemann Sums Equal

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 ......

A New Proof of Foster's First Theorem

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......

A Probabilistic Proof of a Recursion Formula for Sums of Powers

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.

A Proof of Sondow's Conjecture on the Smarandache Function

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 ......

A Note on Fraction Decompositions of Integers

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 ......

The Surprising Accuracy of Benford's Law in Mathematics

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......

共30条页码: 1/2页15条/页