imagine each dozen consist of three horizontal lines: once column 1 or 3 has been hit 2 times in a row in one dozen two quads are placed in the 2 unhit columns in that particular dozen.
negative progression 2 quads: 1,1,1,1,2,2,3,4,5,6,8,10,13,17,22,28...
Linkback: http://www.rouletteforum.cc/index.php?topic=14463.0
negative progression 2 quads: 1,1,1,1,2,2,3,4,5,6,8,10,13,17,22,28...
Linkback: http://www.rouletteforum.cc/index.php?topic=14463.0