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 http://www.math.u-bordeaux.fr/~bruneau. 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
When I was a teenager, I knew the Morpion game like other schoolboys. And also Solitaire with its two versions (cross and octogon) that I liked very much, mainly the octogon because it is more difficult and for which I had solutions without starting from the center. I learned later that we could demonstrate that there is no solution starting from the center! And one day I came across an article in Science & Vie on Morpion Solitaire. I found this game interesting and I remember having played it a lot during my spare time when I was a bachelor's student at Perpignan, during the school year 1974-1975. Being inspired by the previous records (*) published by S&V, I first got 166 moves, then I kept on playing with the hope of improving my score and got 170 in the spring of 1975. Because I progressed, I continued to search again; the summer passed and I left Perpignan for my master's studies in Nice in October 1975 and never played again.
I remember being greatly disappointed by the article with the record of 164 (**) because I already had a much better record... and that's what prompted me to release my own record. When I returned to my parent's home at Perpignan for Christmas, I found my grids and sent in my best one. My grid was handwritten; at that time I had drafts, and I made a good copy on cross-ruled paper from a ring binder that I sent to S&V without even keeping a copy! I did not hear whether it was received, and thought that my grid had not been published. Much later, I met somebody who, learning my name, asked me if I was the Morpion Solitaire player and told me that he had seen my name in S&V. At long intervals, I had some news from other persons interested in this game, then in 2003 Jean-Charles Meyrignac contacted me, and now you tell me that my grid had finally been published in April 1976!
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, www.morpionsolitaire.com