Another number theory Le Monde mathematical puzzles: Find 2≤n≤50 such that the sequence {1,…,n} can be permuted into a sequence such that the sum of two consecutive terms is a prime number. Now this is a problem with an R code solution: which returns the solution as and so it seems there is no solution beyond N=12… […]

## Search Results

## Le Monde puzzle [#840]

November 23, 2013## Le Monde puzzle [#838]

November 2, 2013Another one of those Le Monde mathematical puzzles which wording is confusing to me: The 40 members of the Academy vote for two prizes. [Like the one recently attributed to my friend and coauthor Olivier Cappé!] Once the votes are counted for both prizes, it appears that the total votes for each of the candidates […]

## Le Monde puzzle [#783]

July 21, 2012In a political party, there are as many cells as there are members and each member belongs to at least one cell. Each cell has five members and an arbitrary pair of cells only shares one member. How many members are there in this political party? Back to the mathematical puzzles of Le Monde (science […]

## [not] Le Monde puzzle

April 12, 2012In the spirit of the mathematical puzzles of Le Monde, here is a puzzle that came to me during a family reunion last weekend. During a dinner of 20 couples sitting at four tables with ten seats, everyone wants to share a table with everyone. The assembly decides to switch seats after each serving towards […]

## Le Monde puzzle [website]

September 3, 2011At last, the mathematical puzzles proposed by Buser and Cohen in the weekend edition of Le Monde are available on a dedicated webpage. (The website is in French only and is associated with the math magazine Tangentes.) There is of course a one week delay between the publication of the puzzle in the journal and […]