# Catégorie : Friandises

• ## Jane’s infinite rosary

This mathematical treat was inspired by Jane Street‘s puzzle: Traversing the Infinite Sidewalk. I shared the puzzle with my mathematical friend Éric, and we had quite some fun discovering its properties. It is also a testimony to the richness derived from the irrationality of $$\log_2(3)$$ and reminiscent of about the mathematics underlying the 12-tone Pythagorean […]

• ## Jane’s infinite rosary

This mathematical treat was inspired by Jane Street‘s puzzle: Traversing the Infinite Sidewalk. I shared the puzzle with my mathematical friend Éric, and we had quite some fun discovering its properties. It is also a testimony to the richness derived from the irrationality of $$\log_2(3)$$ and reminiscent of about the mathematics underlying the 12-tone Pythagorean […]

• ## Steiner Triple Systems

[WORK IN PROGRESS] A Steiner Triple System – STS for short – denoted by $\left(X, {\cal T}_X\right)$ is a finite set X together with a set ${\cal T}_X$ of unordered triplets of elements of X – called triples or blocks – with an additional requirement: every (unordered) pair of elements of X must appear in […]

• ## Double détente

C’est pas pire que si c’était moins bien. Rien n’est plus difficile qu’expliquer une chose à une personne quand son salaire dépend de ce qu’elle ne la comprenne pas.

• ## Sudoku with red, yellow and blue

Each row and column must contain the digits 1-9. Digits may not repeat within the outlined regions. Digits may not repeat in cells of the same colour (except white). Digits outside the grid in red are colour sums. The value is the sum of all coloured cells (i.e. non-white) in that row / column. Digits […]

• ## Many lifes

Conway’s Game of Life, emulated in Conway’s Game of Life. The Life pattern is the OTCA Metapixel. The life simulator used is Golly.

• ## Beautiful squares

Normal sudoku rules apply. Additionally, Kropki dots are placed in the grid. Kropki rules are applied only along the grey line (orthogonally or diagonally): adjacent cells containing digits whose difference is 1 are marked with a white circle; adjacent cells containing digits whose ratio is 2 are marked with Black circle; adjacent cells containing digits […]

• ## Christmas tree

Mark Goodliffe and Simon Anthony from cracking the cryptic are doing a fantastic job of making us discover the fascinating world of advanced sudoku. Here is a treat for the season: normal sudoku rules apply, and identical digits cannot be a chess knight’s move apart. The grey square marks an even digit. Any two cages […]