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%I #2 Mar 31 2012 12:38:20
%S 1,5,140,385,2870,8555,29370,42925,93665,116795,149226,155155,348551,
%T 380380,414090,513590,1229305,1801800,2567895,2767905,3873301,3924830,
%U 5053620,6970150,17090486,18362930,23396450,31919165,39336465,41791750
%N Area ar/6 (divided by 6) of primitive Pythagorean triangles such that perimeters are Averages of twin prime pairs, q=p+1, a=q^2-p^2, c=q^2+p^2, b=2*p*q, ar=a*b/2; s=a+b+c, s-+1 are primes.
%C p=1,q=2,a=3,b=4,c=5, ar=3*4/2=6, s=12-+1primes, ...
%t lst={};Do[p=n;q=p+1;a=q^2-p^2;c=q^2+p^2;b=2*p*q;s=a+b+c;ar=a*b/2;If[PrimeQ[s-1]&&PrimeQ[s+1],AppendTo[lst,ar/6]],{n,8!}];lst
%Y Cf. A020882, A020886, A020884, A020883, A024364, A024406, A155171, A155173, A155174, A155175, A155176
%K nonn
%O 1,2
%A _Vladimir Joseph Stephan Orlovsky_, Jan 21 2009