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A358715
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a(n) is the number of distinct ways to cut an equilateral triangle with edges of size n into equilateral triangles with integer sides.
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1
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1, 2, 5, 26, 220, 3622, 105859, 5677789, 553715341, 98404068313, 31850967186980, 18779046566454536, 20167518569123722322, 39451359692134386945019
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OFFSET
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1,2
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COMMENTS
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In other words, the number of equilateral triangular tilings of an equilateral triangle, where rotations and reflections are considered distinct.
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LINKS
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MAPLE
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a(3)=5 because of:
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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