In this post I want to discuss a prime counting sequence similar to OEIS sequence A066888. The sequence A066888 counts the number of primes between 2 consecutive triangular numbers. On the OEIS page of the sequence there is a conjecture that says that there is at least one prime number between 2 consecutive triangular numbers.… Continue reading A Prime Counting Sequence and Andrica’s Conjecture

## The Heptagon, Hyperbola and Lill’s Circle

The heptagon cannot be constructed with just a ruler and a compass. However, in this post I’ll show how you can construct the heptagon using a hyperbola and the Lill’s circle of a third degree polynomial. The heptagon construction is very similar in nature to my trisection construction that I presented in my “Trisection Hyperbolas… Continue reading The Heptagon, Hyperbola and Lill’s Circle

## Trisection Hyperbolas and Lill’s Circle

In my previous blog post about trisection “Angle Trisection: a Neusis Construction using Lill’s Method and Lill’s Circle”, I showed a “mechanical” method for trisecting an angle smaller than 90 degrees. The neusis construction involved the Lill’s method representation of cubic equations of the form x3 -3tan(θ)x2 -3x + tan(θ). These cubic equations have 3 real… Continue reading Trisection Hyperbolas and Lill’s Circle

## The Vertex, Axis of Symmetry and Corresponding Fregier Points for Parabola Points

In my blog post “Frégier’s Theorem and Frégier Points” I introduced Fregier’s theorem. In this post I want to show an alternative way of constructing or finding the corresponding Fregier points for points on a Parabola. This alternative method makes use of the Vertex point and the parabola’s axis of symmetry. I am not sure… Continue reading The Vertex, Axis of Symmetry and Corresponding Fregier Points for Parabola Points

## Whittaker’s Root Series: Going Transcendental

Whittaker’s Root Series formula is an interesting method that can be used to calculate the root with the smallest absolute value of a polynomial equation. The formula creates a geometrically convergent infinite series using the determinants of a special class of Toeplitz matrices. These Toeplitz matrices are generated using the coefficients of the polynomial equation.… Continue reading Whittaker’s Root Series: Going Transcendental

## Angle Trisection: a Neusis Construction using Lill’s Method and Lill’s Circle

The problem of trisecting an angle using just a compass and a straightedge is an impossible problem. However, the problem of angle trisection can be solved if we are allowed the use of a marked ruler. Geometric constructions that use a marked ruler are called neusis constructions. You can learn more about the topic of… Continue reading Angle Trisection: a Neusis Construction using Lill’s Method and Lill’s Circle

## Symbolic Literacy: Justice and the Ostrich

Egyptians were the first to symbolically associate the ostrich with justice. Maat, the goddess of justice, is usually depicted wearing an ostrich feather. The image above shows a scene from the Book of the Dead that depicts the “Weighting of the heart” ritual. In the “Weighting of the heart’ ritual, the heart of of the… Continue reading Symbolic Literacy: Justice and the Ostrich

## Discussing a Few of My Favorite Paintings

I am not an artist, but I love art. As an amateur mathematician who is interested in geometry (also Lill’s method), it should not be a surprise that I am interested in visual arts. One of my main hobbies is trying to discover interesting paintings, especially paintings created before 20th century. I am not a… Continue reading Discussing a Few of My Favorite Paintings

## 2 Interesting Kickstarter Projects

Recently I finally decided to create a Kickstarter account to back up 2 projects that I discovered while browsing the website. My website is too small to help the 2 funding campaigns, nonetheless I want to share a few thoughts about the two projects. The Frogs by Michael Wells “The Frogs” is a point-and-click adventure… Continue reading 2 Interesting Kickstarter Projects

## My archive.org Collection

On archive.org I have a small collection of scanned books or brochures. Right now I only have 7 uploads and they are in Romanian or English. For convenience I will embed the scanned materials on this page and maybe I will give a short description. The Dutch and Flemish Cabinet Galleries (National Gallery of Art… Continue reading My archive.org Collection