Function Repository Resource:

# TriangularSpiralPoints

Get the coordinates of the points on a triangular spiral

Contributed by: George Beck
 ResourceFunction["TriangularSpiralPoints"][n] gives the list of coordinate pairs on an equilateral triangular spiral with n sides starting at the origin.

## Details and Options

The list starts at the origin and goes (roughly) NW, SW, E and repeats.

## Examples

### Basic Examples (4)

Here are the points on the first four legs of the spiral:

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This shows the sequence of points in order for the first six sides:

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40 black sides with 20 red sides overlaid:

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The number of points in the first n sides are one more than the triangular numbers:

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### Neat Examples (2)

This finds the coordinate pairs that are a prime distance along the square spiral:

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The larger points correspond to the primes 2, 3, 5, 7, 11:

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About 12% of the numbers up to 11326 are prime:

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Here is a plot of the first 1369 primes:

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About 11% of the numbers up to 11326 are lucky:

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This finds the coordinate pairs that are at lucky number distances along the triangular spiral:

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Here are the first 1248 lucky numbers plotted along the triangular spiral:

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George Beck

## Requirements

Wolfram Language 11.3 (March 2018) or above

## Version History

• 1.0.0 – 26 February 2019