A070141 Number of obtuse integer triangles with perimeter n having integral area.

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

Offset: 1

Author

Reinhard Zumkeller, May 05 2002

Keywords

• nonn

Comments

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

Links

• 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.