English: Triangular dominoes, as described by Frank Richards in US Patent 331,652 (1885). The dominoes are marked with pips on each side and the sum of the pips in the center. The filename embeds the pip configuration "TriDominoes Richards XYZ", where:
X = number of pips on lower edge
Y = number of pips on upper right edge
Z = number of pips on upper left edge
In the patent, Richards describes two sets of 24 (pip values ranging from 0 to 4) or 56 (pips 0 - 5), described in a way so the numbers are always increasing when written starting with the lowest value (i.e., 123 is possible but not 132). The figures accompanying the patent show the pip values increase (or are equal) when counted in a clockwise fashion, starting from the lowest value(s). These drawings show the pip values increasing (or equal) when counted in an anti-clockwise direction.
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Mliu92
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