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A120261
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Number of primitive triangles with integer sides a<=b<=c and inradius n; primitive means gcd(a, b, c) = 1.
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2
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1, 4, 10, 11, 13, 28, 17, 26, 31, 31, 20, 77, 28, 46, 67, 40, 28, 100, 26, 72, 120, 62, 32, 139, 44, 53, 71, 118, 32, 202, 35, 70, 135, 73, 97, 211, 33, 80, 130, 134, 36, 284, 45, 141, 183, 78, 50, 226, 68, 112, 150, 146, 38, 173, 150, 219, 182, 80, 38, 468, 36, 82
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| David W. Wilson, Table of n, a(n) for n = 1..10000
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EXAMPLE
| a(3)=10 because 10 triangles have coprime integer sides and inradius 3, namely (7,24,25) (7,65,68) (8,15,17) (11,13,20) (12,55,65) (13,40,51) (15,28,41) (16,25,39) (19,20,37) (11,100,109).
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CROSSREFS
| Cf. A120062, A120252.
See A120062 for sequences related to integer-sided triangles with integer inradius n.
Sequence in context: A102535 A074226 A106631 * A101154 A182943 A090070
Adjacent sequences: A120258 A120259 A120260 * A120262 A120263 A120264
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KEYWORD
| nonn
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AUTHOR
| David W. Wilson (davidwwilson(AT)comcast.net), Jun 13 2006
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