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A101930 Number of Pythagorean triples with hypotenuse <= 10^n. 3

%I

%S 2,52,881,12471,161436,1980642,23471475,271360653,3080075432,

%T 34465432859,381301109919,4179478903392,45459467009968,

%U 491241450001328,5278882299478796,56453500988940615,601181789833245631

%N Number of Pythagorean triples with hypotenuse <= 10^n.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PythagoreanTriple.html">Pythagorean Triple</a>

%F a(n) = A101929(n) + n. - _Robert G. Wilson v_, Mar 20 2014

%o (PARI) a(n)=my(t,lim=10^n);for(m=2,sqrtint(lim-1),forstep(n=1+m%2,min(sqrtint(lim-m^2),m-1),2,if(gcd(m,n)==1,t+=lim\(m^2+n^2))));t \\ _Charles R Greathouse IV_, Sep 13 2012

%Y Cf. A101929.

%K nonn,more

%O 1,1

%A _Eric W. Weisstein_, Dec 21 2004

%E Corrected by Todd Stedl (tstedl(AT)speakeasy.net), Jan 15 2005

%E More terms from Jan Feitsma and Bart Dopheide (dopheide(AT)fmf.nl), Mar 10 2005

%E a(10)-a(11) from _Charles R Greathouse IV_, Sep 14 2012

%E a(12) from _Charles R Greathouse IV_, Oct 15 2012

%E a(13)-a(17) from _Hiroaki Yamanouchi_, Jul 14 2014

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Last modified December 13 17:54 EST 2018. Contains 318086 sequences. (Running on oeis4.)