The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A101930 Number of Pythagorean triples with hypotenuse <= 10^n. 3
 2, 52, 881, 12471, 161436, 1980642, 23471475, 271360653, 3080075432, 34465432859, 381301109919, 4179478903392, 45459467009968, 491241450001328, 5278882299478796, 56453500988940615, 601181789833245631, 6378285697775544230 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..18. Eric Weisstein's World of Mathematics, Pythagorean Triple FORMULA a(n) = A101929(n) + n. - Robert G. Wilson v, Mar 20 2014 PROG (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 CROSSREFS Cf. A101929. Sequence in context: A053317 A123803 A284767 * A297756 A174779 A215744 Adjacent sequences: A101927 A101928 A101929 * A101931 A101932 A101933 KEYWORD nonn,more AUTHOR Eric W. Weisstein, Dec 21 2004 EXTENSIONS Corrected by Todd Stedl (tstedl(AT)speakeasy.net), Jan 15 2005 More terms from Jan Feitsma and Bart Dopheide (dopheide(AT)fmf.nl), Mar 10 2005 a(10)-a(11) from Charles R Greathouse IV, Sep 14 2012 a(12) from Charles R Greathouse IV, Oct 15 2012 a(13)-a(17) from Hiroaki Yamanouchi, Jul 14 2014 a(18) from Matan M. Atzmoni, Feb 04 2023 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified August 13 02:28 EDT 2024. Contains 375113 sequences. (Running on oeis4.)