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Inradii of integer triangles [A070080(n), A070081(n), A070082(n)], rounded values.

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0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 0, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 2, 0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 1, 2, 2, 2, 0, 1, 1, 1, 1, 2, 1, 2, 2, 2, 2, 2, 1, 1, 1, 2, 1, 2 (list; graph; listen)

	OFFSET	`1,39`
	COMMENT	`Triangles [A070080(A070209(n)), A070081(A070209(n)), A070082(A070209(n))] have integer inradii = a(A070209(k))= A070210(k).`
	LINKS	`Eric Weisstein's World of Mathematics, Incircle.` `R. Zumkeller, Integer-sided triangles`
	FORMULA	`a(n) = SquareRoot((s-u)(s-v)(s-w)/s), where u=A070080(n), v=A070081(n), w=A070082(n) and s=A070083(n)/2=(u+v+w)/2.`
	EXAMPLE	`[A070080(25), A070081(25), A070082(25)]=[3,5,6] and s=A070083(25)/2=(3+5+6)/2=7: a(25)=SquareRoot((s-3)(s-5)(s-6)/7) = SquareRoot((7-3)(7-5)(7-6)/7) = SquareRoot(421/7) = SquareRoot(8/7) = 1.069, rounded = 1.`
	CROSSREFS	`Cf. A070086.` `Sequence in context: A105241 A134541 A144474 this_sequence A025914 A025916 A025905` `Adjacent sequences: A070197 A070198 A070199 this_sequence A070201 A070202 A070203`
	KEYWORD	`nonn`
	AUTHOR	`Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 05 2002`

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Last modified November 21 14:49 EST 2008. Contains 150807 sequences.

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