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%I #11 Feb 01 2021 19:08:54
%S 12,16,18,30,32,36,40,42,44,48,50,54,56,60,64,68,70,72,76,78,80,84,90,
%T 96,98,100,104,108,110,112,114,120,126,128,130,132,136,140,144,150,
%U 152,154,156,160,162,164,168,170,172,176,180,182,186,190,192,196,198,200,204,208
%N Perimeters of Heronian triangles where the lengths of the middle and largest sides are coprime.
%C This sequence includes the perimeters of all primitive Heronian triangles (A096468). First differs from A096468 at a(16) = 68.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HeronianTriangle.html">Heronian Triangle</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Heronian_triangle">Heronian triangle</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Integer_triangle">Integer Triangle</a>
%e a(1) = 12; there is one Heronian triangle with perimeter 12, which is [3,4,5] and the lengths of the middle and largest sides are coprime (GCD(4,5) = 1).
%e a(5) = 32; there is one Heronian triangle with perimeter 32, [4,13,15] and the lengths of the smallest and middle sides are coprime (GCD(4,13) = 1).
%Y Cf. A051518, A096468, A334983, A334989.
%K nonn
%O 1,1
%A _Wesley Ivan Hurt_, May 18 2020