Morpion Solitaire - Bruneau's Grid (5T game), the world record from 1976 to 2010

Charles-Henri Bruneau (Perpignan, France 1953 - ) in 2008

April 1976: Science & Vie published a Morpion Solitaire grid done by Charles-Henri Bruneau, without any computer. With its 170 moves, it was for 34 years, the world record at the original 5T game! It was only in August 2010 that his record was beaten by Rosin's grid of 172 moves, obtained with a computer. Charles-Henri Bruneau is now professor at the I.M.B. (Institut de Mathématiques de Bordeaux, University of Bordeaux 1). His home page is Two astonishing facts:

Bernard Helmstetter, in his thesis of February 2007 ("Analyses de dépendances et méthodes de Monte-Carlo dans les jeux de réflexion"), studied Bruneau's grid, and found it optimal for its last 109 moves. If his computing is correct, it is impossible to get a better score for any play starting from the 61st move of this grid! An impressive result for a grid created by hand.

On the left: C.-H. Bruneau's grid of 170 moves obtained with Pentasol
On the right: same grid as published by Pierre Berloquin in Science & Vie, April 1976, page 130.
Slight errors made by the magazine: the horizontal lines between 155-165-164 moves should not be drawn and the vertical line between 159-154 moves should be drawn.
(click on the images to enlarge them)

Denis Excoffier copied Bruneau's grid in 2000, from the 1st to the 170th move. There is another grid of 170 moves, apparently done in January 1982 by J.-B. Bonté, never published in a magazine. This grid, very close to Bruneau's grid, was sent by Pierre Berloquin to Jean-Charles Meyrignac in 2003:

J.-B. Bonté's grid of 170 moves

Before Bruneau's grid, the previous records were done in 1975 independantly by Joseph Martin, Michel Szeps and Yoland Strehl with grids of 164 moves.

Story of the Bruneau's grid

Incredible! Charles-Henri Bruneau did not know that his own grid had been published!

More than 30 years after its publication, I was very pleased to send him the information in my email of January 23, 2008.... Of course, he remembered that he had reached this score of 170 moves and to have sent the grid to Science & Vie, but he thought (and was disappointed) that his grid had never been published... He only knew that his name with his score had been mentioned -without the grid- in some websites and papers (for example in Jeux & Stratégie). Here is Pierre Berloquin's column that he had never seen, presenting his grid:

Science & Vie, April 1976: publication of Bruneau's grid of 170 moves, by Pierre Berloquin
(click on the images to enlarge them, or download the PDF file, 2.4Mb)

Asking Charles-Henri Bruneau to tell me the history of his grid, here is what he remembers (translated in English):

Charles-Henri Bruneau in 1970s

During the summer of 2008, Pierre Berloquin honoured me by entrusting his archives to me: I was very happy to find Bruneau's original letter, including his grid which has been during 34 years the world record! Here is this "historic" letter which was written on January 2nd 1976 (the author C.H. Bruneau, happy that his writing has been found, authorize me to publish it here):

Original letter of Charles-Henri Bruneau sent to Science & Vie, Pierre Berloquin's column
(click on the images to enlarge them)

© Christian Boyer,