A338201 a(n) is the number of unit perimeter triangles with rational side lengths whose largest denominator is equal to n.
0, 0, 1, 0, 1, 0, 2, 1, 2, 1, 4, 2, 5, 2, 5, 4, 8, 4, 10, 8, 10, 6, 14, 8, 15, 9, 16, 14, 21, 13, 24, 16, 23, 16, 41, 18, 33, 20, 33, 32, 40, 32, 44, 34, 53, 30, 52, 32, 54, 35, 54, 48, 65, 38, 87, 70, 67, 49, 80, 64, 85, 56, 116, 64, 116, 73, 102, 80, 96, 99
Offset: 1
Keywords
Examples
For n = 20, the a(20) = 8 triangles have sides: 1/4, 7/20, 2/5; 1/12, 9/20, 7/15; 3/10, 7/20, 7/20; 3/20, 2/5, 9/20; 1/4, 3/10, 9/20; 2/15, 5/12, 9/20; 1/5, 7/20, 9/20; and 1/10, 9/20, 9/20.
Links
- Peter Kagey, Table of n, a(n) for n = 1..300
- Code Golf Stack Exchange, Triangles with rational side lengths
- Peter Kagey, Haskell program.
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