( Scarthin Books, my some days job, is in the middle of a crowdfunding exercise to Prop up the Shop, its over a mile of bookshelves and its 40 tons or so of books. Cunningly inserted, secret Acrow props have done the job for many years but are now being supplemented by properly designed, well-foundationed and visible circular steel columns each 114.3 mm (a ghostly 4½ inches) in diameter. We have been overwhelmed by the level of support ( so far about £2.50 for every week of the bookshop’s existence) and the messages of goodwill that have accompanied the pledges.)
The first tessellation is a thankyou for their pledge to A.J. and S.J., who were wed on April 13th.
The separation parameters (13,4) imply that each hexagonally symmetrical supertile is made up of 2( 13² + 13×4 + 4²) = 474 equilateral triangles. The re-drawing of the tessellation makes its structure clearer.
Thirteen days later, give or take a few years, I. S. , a vigorous mathematical blogger, was wed on April 26th. and here is her anniversary tessellation for separation parameters (26,4); a Trefoil Lattice Labyrinth because 26² + 26×4 + 4² = 796 is of the form 3n+1. The American date style (4,26) is simply the mirror reflection of (26,4), shown below.
and here is a version that elucidates its structure.
The usual link to my How to do it workbook. Or I can maybe give your group a talk.