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A070141 Number of obtuse integer triangles with perimeter n having integral area. 3
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 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, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 3, 0, 0, 0, 0, 0, 1, 0, 0, 0, 3, 0, 1, 0, 0, 0, 0, 0, 3, 0, 0, 0, 1, 0, 1, 0, 2, 0, 0, 0, 4, 0, 0, 0, 1, 0, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,36

COMMENTS

a(n) = A051516(n) - A070140(n) - A024155(n).

LINKS

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

Eric Weisstein's World of Mathematics, Heronian Triangle.

Eric Weisstein's World of Mathematics, Obtuse Triangle.

R. Zumkeller, Integer-sided triangles

CROSSREFS

Cf. A051516, A070101, A070147.

Sequence in context: A082786 A101638 A321379 * A088722 A122180 A033772

Adjacent sequences:  A070138 A070139 A070140 * A070142 A070143 A070144

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, May 05 2002

STATUS

approved

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Last modified April 19 21:09 EDT 2019. Contains 322291 sequences. (Running on oeis4.)