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A070210
Inradii of integer triangles [A070080(A070209(n)), A070081(A070209(n)), A070082(A070209(n))].
2
1, 2, 2, 3, 2, 3, 3, 2, 4, 3, 4, 4, 3, 2, 4, 5, 3, 6, 4, 6, 6, 6, 4, 6, 3, 4, 3, 6, 4, 5, 4, 3, 6, 5, 7, 8, 6, 4, 6, 8, 7, 8, 9, 3, 9, 5, 6, 9, 8, 10, 6, 6, 6, 9, 8, 4, 8, 9, 7, 10, 6, 10, 12, 6, 12, 12, 5, 3, 7, 8, 10, 4, 9, 10, 11, 6, 12, 3, 6, 9, 12, 12, 7, 8
OFFSET
1,2
COMMENTS
a(n) = A070200(A070209(n)).
LINKS
Mohammad K. Azarian, Solution of problem 125: Circumradius and Inradius, Math Horizons, Vol. 16, No. 2 (Nov. 2008), p. 32.
Eric Weisstein's World of Mathematics, Incircle.
EXAMPLE
A070209(3)=212: [A070080(212), A070081(212), A070082(212)] = [5,12,13], let s = A070083(212)/2 = (5+12+13)/2 = 15 then inradius = sqrt((s-5)*(s-5)*(s-6)/s) = sqrt(10*3*2/15) = sqrt(4) = 2; a(3) = A070200(212) = 2.
CROSSREFS
Sequence in context: A376569 A375312 A081308 * A100198 A164996 A216195
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, May 05 2002
STATUS
approved