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A120570
Smallest perimeter of triangles with integer sides and inradius n.
4
12, 24, 32, 42, 60, 64, 84, 84, 96, 108, 132, 126, 156, 162, 156, 168, 204, 190, 228, 210, 220, 240, 276, 250, 300, 312, 288, 294, 348, 312, 372, 336, 352, 408, 372, 378, 444, 456, 416, 420, 492, 440, 516, 462, 468, 552, 564, 500, 588, 540, 544, 546, 636, 570
OFFSET
1,1
COMMENTS
Empirically, 6*sqrt(3) <= a(n)/n <= 12. The lower bound is provably tight.
a(n) == 0 (mod 4).
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
CROSSREFS
See A120062 for sequences related to integer-sided triangles with integer inradius n.
Sequence in context: A261435 A103590 A081699 * A164014 A336772 A098113
KEYWORD
nonn
AUTHOR
David W. Wilson, Jun 17 2006
STATUS
approved