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A120569
Number of isosceles triangles with integer sides and inradius n.
1
0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 3, 0, 0, 2, 1, 0, 1, 0, 2, 2, 0, 0, 5, 0, 0, 1, 1, 0, 3, 0, 1, 1, 0, 1, 4, 0, 0, 1, 3, 0, 3, 0, 1, 2, 0, 0, 5, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 8, 0, 0, 3, 1, 0, 1, 0, 1, 1, 2, 0, 6, 0, 0, 2, 1, 0, 2, 0, 3, 1, 0, 0, 6, 0, 0, 1, 1, 0, 4, 0, 1, 1, 0, 0, 5, 0, 0, 2, 2, 0, 1, 0, 1, 5
OFFSET
1,12
REFERENCES
Mohammad K. Azarian, Circumradius and Inradius, Problem S125, Math Horizons, Vol. 15, Issue 4, April 2008, p. 32. Solution published in Vol. 16, Issue 2, November 2008, p. 32.
LINKS
EXAMPLE
a(24) = 5 because 5 integer-sided isosceles triangles, namely (a,b,c) = (80,80,96), (80,85,85), (90,90,144), (130,130,240), (175,175,336), have inradius 24.
CROSSREFS
See A120062 for sequences related to integer-sided triangles with integer inradius n.
Sequence in context: A115979 A067168 A099475 * A128113 A108930 A059682
KEYWORD
nonn
AUTHOR
David W. Wilson, Jun 17 2006
STATUS
approved