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A070139 Number of isosceles integer triangles with perimeter n having integral area. 2
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 2, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,36

COMMENTS

a(n) = A051516(n) - A024153(n).

LINKS

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

Eric Weisstein's World of Mathematics, Heronian Triangle.

R. Zumkeller, Integer-sided triangles

CROSSREFS

Cf. A051516, A024153, A059169, A070145.

Sequence in context: A027345 A086080 A281477 * A116860 A179391 A083850

Adjacent sequences:  A070136 A070137 A070138 * A070140 A070141 A070142

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, May 05 2002

STATUS

approved

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Last modified October 17 10:50 EDT 2017. Contains 293469 sequences.