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A070090 Number of scalene integer triangles with perimeter n and prime side lengths. 5
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,35

COMMENTS

a(n) = A070088(n) - A070092(n).

LINKS

Table of n, a(n) for n=1..90.

R. Zumkeller, Integer-sided triangles

EXAMPLE

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.

CROSSREFS

Cf. A070080, A070081, A070082, A005044, A070097, A070105, A070114.

Sequence in context: A286351 A091394 A029881 * A230642 A053473 A208459

Adjacent sequences:  A070087 A070088 A070089 * A070091 A070092 A070093

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, May 05 2002

STATUS

approved

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Last modified October 19 22:00 EDT 2018. Contains 316378 sequences. (Running on oeis4.)