Dominos sets containing an even number of dominos - double 2, 3, 6, 7 etc - can form dominos squares. Dominos sets containing odd numbers of dominos - double 4, 5, 8 etc - can form dominos rectangles whose long sides contain one more half-domino than their short sides. Either way, if the double is also even the dominos form can have all its joins match.
Dominos Double 4
_______ _______ _______ _______ | | || | || | || | | |___|___||___|___||___|___||___|___| ___ ___ | | | | |___| |___| _______ _______ | | | | | | || | | |___| |___| |___|___||___|___| ___ Joins match OR ___ ___ ___ | | sides have equal | | | | | | |___| number of dots |___| |___| ______ |___| | | | | | || | || | |___| |___| |___||___|__||___| ___ ___ | | | | 5 of these |___| |___| little squares: | | | | Joins match OR |___| |___| All 12 sides have ___ ___ same number of dots | | | | |___| _______ _______ ______ |___| | || | || | || | || | |___||___|___||___|___||___|__||___|
Dominos sets from Double 6 up in which the largest double domino is an even number, can form suqares or near-square rectangles with matching joins and equal numbers of dots. This is not possible with the double 4 dominos set.
Dominos sides have equal number of dots
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Dominos Double 5
_______ _______ _______ _______ _______ ___ | | || | || | || | || | || | |___|___||___|___||___|___||___|___||___|___||___| ___ | | | | |___| |___| ___ | | | | |___| |___| ___ | | | | |___| |___| ___ | | | | |___| |___| ___ | | | | |___| |___| ___ | | | | |___| |___| ___ | | | | |___| |___| ___ | | | | |___| |___| ___ | | | | |___| |___| ___ | | | | |___| |___| _______ _______ _______ _______ _______ | | | | || | || | || | || | ||___| |___|___||___|___||___|___||___|___||___|___| _______ _______ ___ | | || | || | |___|___||___|___||___| ___ | | 3 dominos rectangles | | |___| All 12 sides have |___| ___ same number of dots | | | | |___| |___| _______ _______ | | | | || | ||___| |___|___||___|___|