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%I #4 Mar 30 2012 18:52:25
%S 7,15,20,42,7,24,25,84,13,14,15,84,13,84,85,546,17,8,15,60,17,9,10,36,
%T 29,20,21,210,37,12,35,210,41,9,40,180,53,45,48,1080,73,48,55,1320,89,
%U 39,80,1560,97,65,72,2340,101,20,99,990,109,60,91,2730,113,15,112,840
%N Quartets of prime x, composites y, z and S for Heron's formula.
%C Heron's formula (x+y+z)*(x+y-z)*(x+z-y)*(y+z-x)/16=S^2
%e The quartets are: (7, 15, 20, 42), (7, 24, 25, 84), (13, 14, 15, 84), etc.
%Y Cf. A140385, A140391, A140384.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Jul 10 2008
%E This should be replaced by four linked sequences! As it stands it is not a proper sequence. - _N. J. A. Sloane_, Jul 11 2008
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