John D. Cook

When I hear the term ultraspherical I think of something extremely spherical.

The previous post gave several examples of three-term recurrence relations for special functions.

There many examples of families of functions where each function can be computed as a linear combination of the two previous terms where a and b are functions of x and possibly n.

Probability density function must integrate to 1, and so if you know a density function up to a constant, the constant is determined.

Special functions often have arcane names that not very helpful without some context.

Special functions are special because they’re useful.

Suppose you wanted to find the distance between Earth and Mars over time.

There’s a pizza shop near my home with a sign out front that says “Coming Soon.”

A few weeks ago I wrote about the number system used in labeling spreadsheet columns.

I like AI-generated ASCII diagrams.

A new paper just came out, The Maximum-Area Small Polygon Problem.

The imbalance conjecture is now a theorem.

Suppose you have a planet in an elliptical orbit around a star.

The first post in the recent series of posts on Hadamard matrices describes a way of constructing new Hadamard matrices from two other Hadamard matrices by taking their Kronecker product.

Error correcting codes are most simply described in terms of the errors they can certainly correct.