Morpion Solitaire - Other Records Grids (5T and 5D games)

In the 5T and 5D games, the initial pattern is a cross using 36 dots. But is it possible to get a better score than the current records of 172 moves (5T) and 82 moves (5D) from another initial pattern using the same number of dots (36)? The answer is not obvious, but yes!

Who will find a grid with more than 187 moves (5T) or more than 102 moves (5D) from an initial pattern using 36 dots? Send me a message!

The first published 5T example is a very nice symmetrical grid giving 182 moves, created in 1975 by M. Duloquin of Bry sur Marne. His full first name was not given in Science & Vie, but I succeeded in finding him in February 2010: 35 years after the publication of his grid, he was very surprised of my phone call... His first name is Michel.


Michel Duloquin's 5T grid of 182 moves as published by Pierre Berloquin in Science & Vie, May 1975, page 134.
Published as a game: will you succeed in completing the missing numbers of moves?
(click on the image to enlarge it)

Six months later, in November 1975, Pierre Berloquin announced a better grid of 186 moves by R. Féron, unfortunately without publishing it. I was able to find this grid in Berloquin's archives! And thanks to the letter dated May 20th 1975 associated with the grid, this mysterious "R. Féron" is in fact Robert Féron, professor at the Université de Lyon, famous for his research on probability and statistics (on him, see the paper of Jean-Paul Auray and Henri Prade published in 2008 in Advances in Soft Computing). Here is his small piece of ruled paper:


Original of the 5T grid of "186" moves by Robert Féron, sent to Pierre Berloquin in 1975
(click on the image to enlarge it)

By looking at it, we may think that he made a mistake, because we can discern (with difficulty) 37 initial dots instead of 36. But, after careful checking, we see he used only 36 dots. On the other hand, his real score is only 185 moves, instead of 186 as announced. Here is his grid, as I have reconstructed it:


5T grid of 185 moves by Robert Féron, rebuilt in February 2010 by Christian Boyer
(click on the image to enlarge it)

Marc Lapierre in 2007 (Versailles 1970 -)

In February 2008, Marc Lapierre, France, constructed this grid of 187 moves, inspired by the Duloquin grid. This is the current record!


February 2008: 5T grid of 187 moves by Marc Lapierre.
(click on the image to enlarge it)

My first best 5D score from a pattern of 36 dots was initially 100 moves, with this grid:


February 2008: 5D grid of 100 moves by Christian Boyer.
(click on the image to enlarge it)

later slightly improved with one more move:


January 2010: 5D grid of 101 moves by Christian Boyer.
(click on the image to enlarge it)

Peter Bartsch in 2010 (West-Berlin 1947 - )

Then, Peter Bartsch, Germany, improved again the score with one more move, directly using my above pattern of 36 dots. Congratulations to him... and hmmm... shame on me to have been unable to find this solution from my own pattern!


August 23rd, 2010: 5D grid of 102 moves by Peter Bartsch.
(click on the image to enlarge it)

© Christian Boyer, www.morpionsolitaire.com