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%I #6 Jul 01 2014 09:31:16
%S 2,9,7,4,6,1,5,5,2,9,8,1,2,6,0,1,8,8,9,7,1,4,6,2,4,0,2,2,7,0,1,4,7,6,
%T 7,9,8,3,2,8,4,7,0,5,4,2,2,9,5,5,1,1,9,6,7,2,9,6,7,1,7,3,8,8,4,0,1,9,
%U 8,2,4,7,7,9,3,1,0,5,0,5,0,4,1,8,4,7,9,9,6,7,4,2,4,2,2,8,0,1,4,5,0,7,4
%N Decimal expansion of the coefficient D appearing in the asymptotic evaluation of P_a(n), the number of primitive Pythagorean triples whose area does not exceed a given bound n.
%D Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 5.2 Pythagorean Triple Constants, p. 277.
%H Eric Weisstein's MathWorld, <a href="http://mathworld.wolfram.com/PrimitivePythagoreanTriple.html">Primitive Pythagorean Triple</a>
%F P_a(n) = C*n^(1/2) - D*n^(1/3) + O(n^(1/4)*log(n)).
%F D = -((1 + 1/2^(1/3))*zeta(1/3)/((1 + 1/4^(1/3))*zeta(4/3))).
%e 0.2974615529812601889714624022701476798328470542295511967296717388401982...
%t -((1 + 1/2^(1/3))*Zeta[1/3]/((1 + 1/4^(1/3))*Zeta[4/3])) // RealDigits[#, 10, 103]& // First
%Y Cf. A242439.
%K nonn,cons,easy
%O 0,1
%A _Jean-François Alcover_, Jul 01 2014