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A070103
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Number of obtuse integer triangles with perimeter n and prime side lengths.
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6
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0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 2, 0, 1, 0, 0, 0, 0, 0, 2, 0, 1, 0, 3, 0, 2, 0, 2, 0, 1, 0, 3, 0, 2, 0, 1, 0, 2, 0, 0, 0, 0, 0, 3, 0, 1, 0, 4, 0, 5, 0, 4, 0, 2, 0, 1, 0, 1, 0, 2, 0, 2, 0, 3, 0, 1, 0, 6, 0, 4, 0, 6, 0, 6, 0
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,27
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COMMENTS
| a(n) = A070093(n) - A070098(n).
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LINKS
| R. Zumkeller, Integer-sided triangles
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EXAMPLE
| For n=11 there are A005044(11)=4 integer triangles: [1,5,5], [2,4,5], [3,3,5] and [3,4,4]; only one of the two obtuses ([2,4,5] and [3,3,5]) consists of primes, therefore a(11)=1.
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CROSSREFS
| Cf. A070080, A070081, A070082, A070101, A070088, A070105, A070108, A070129.
Sequence in context: A060396 A195470 A045827 * A113048 A123758 A069846
Adjacent sequences: A070100 A070101 A070102 * A070104 A070105 A070106
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KEYWORD
| nonn
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AUTHOR
| Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 05 2002
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