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A070787 Number of triangles with sides whose squares are integers and with positive integer area and longest side of length sqrt(n). 5

%I #2 Mar 30 2012 18:51:38

%S 0,0,0,1,2,0,0,2,1,4,0,1,3,0,2,5,5,2,0,13,0,0,0,2,9,8,1,1,9,4,0,10,0,

%T 10,2,12,11,0,3,23,14,0,0,1,13,0,0,5,5,18,5,32,18,2,2,2,0,19,0,13,16,

%U 0,1,20,35,0,0,42,0,4,0,23,24,23,9,1,0,8,0,44,10,27,0,1,48,0,9,2,27,25,3

%N Number of triangles with sides whose squares are integers and with positive integer area and longest side of length sqrt(n).

%H A. Bogomolny, <a href="http://www.cut-the-knot.com/pythagoras/Loyds.shtml">Sam Loyd's Geometric Puzzle</a>

%e a(13)=3 since the 3 triangles with sides {sqrt(13), sqrt(5), sqrt(4)}, {sqrt(13), sqrt(8), sqrt(1)} and {sqrt(13), sqrt(9), sqrt(4)} have areas 2, 1 and 3 respectively.

%Y Cf. A054875, A070783, A070784, A070785, A070786.

%K nonn

%O 1,5

%A _Henry Bottomley_, May 07 2002

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