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A070149 Areas of integer Heronian triangles [A070080(A070142(n)), A070081(A070142(n)), A070082(A070142(n))]. 3
6, 12, 12, 24, 30, 24, 48, 36, 54, 48, 60, 60, 42, 84, 66, 84, 96, 108, 60, 120, 36, 90, 126, 108, 84, 60, 120, 150, 72, 96, 168, 120, 192, 132, 204, 210, 210, 84, 144, 216, 192, 240, 114, 156, 180, 120, 240, 300, 168, 210, 168 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

a(n) = A070086(A070142(n)).

LINKS

R. Zumkeller, Integer-sided triangles

Eric Weisstein's World of Mathematics, Heronian Triangle.

EXAMPLE

A070142(2)=39: [A070080(39), A070081(39), A070082(39)] = [5,5,6], area^2 = s*(s-5)*(s-5)*(s-6) with s=A070083(39)/2=(5+5+6)/2=8, area^2=8*3*3*2=16*9 is an integer square, therefore a(2)=A070086(39)=area=4*3=12.

CROSSREFS

Cf. A070142, A070210.

Sequence in context: A205972 A129858 A061928 * A181798 A183688 A055595

Adjacent sequences:  A070146 A070147 A070148 * A070150 A070151 A070152

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 05 2002

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Last modified February 14 11:36 EST 2012. Contains 205623 sequences.