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A070090
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Number of scalene integer triangles with perimeter n and prime side lengths.
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5
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0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 2, 0, 1, 0, 2, 0, 2, 0, 2, 0, 0, 0, 4, 0, 2, 0, 1, 0, 2, 0, 1, 0, 0, 0, 4, 0, 1, 0, 3, 0, 4, 0, 3, 0, 1, 0, 3, 0, 2, 0, 1, 0, 3, 0, 4, 0, 1, 0, 6, 0, 4, 0, 5, 0, 6, 0
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OFFSET
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1,35
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COMMENTS
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a(n) = A070088(n) - A070092(n).
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LINKS
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Table of n, a(n) for n=1..90.
R. Zumkeller, Integer-sided triangles
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EXAMPLE
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For n=15 there are A005044(15)=7 integer triangles: [1,7,7], [2,6,7], [3,5,7], [3,6,6], [4,4,7], [4,5,6] and [5,5,5]: three are scalene: [2<6<7], [3<5<7] and [4<5<6], but only one consists of primes, therefore a(15)=1.
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CROSSREFS
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Cf. A070080, A070081, A070082, A005044, A070097, A070105, A070114.
Sequence in context: A049767 A091394 A029881 * A053473 A208459 A144764
Adjacent sequences: A070087 A070088 A070089 * A070091 A070092 A070093
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KEYWORD
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nonn
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AUTHOR
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Reinhard Zumkeller, May 05 2002
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STATUS
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approved
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