Today’s advent calendar window is covered in snowflakes! These snowflakes aren’t your usual sort, however – they’re made up of thousands of toothpicks arranged into E shapes. Hey, nobody mixes metaphors like mathematicians.

The image above shows 1,124 E-shapes arranged rather artfully. 1,124 is the 32nd entry of the sequence A161330, which lists how many shapes are used at each stage of the construction of the snowflake.

The Online Encyclopedia of Integer Sequences has recently made a page showing off many of the prettier pictures contributors have made to illustrate sequences, of which the snowflake above is just one. The idea is that rather than running their own shop selling t-shirts, you can just grab an image off that page and make your own. How in fitting with the giving season!

This is part of the Aperiodical Advent Calendar. We’ll be posting a new surprise for you each morning until Christmas!