

A020883


Ordered long legs of primitive Pythagorean triangles.


44



4, 12, 15, 21, 24, 35, 40, 45, 55, 56, 60, 63, 72, 77, 80, 84, 91, 99, 105, 112, 117, 120, 132, 140, 143, 144, 153, 156, 165, 168, 171, 176, 180, 187, 195, 208, 209, 220, 221, 224, 231, 240, 247, 252, 253, 255, 260, 264, 272, 273, 275, 285, 288, 299, 304, 308, 312, 323
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OFFSET

1,1


COMMENTS

Consider primitive Pythagorean triangles (A^2 + B^2 = C^2, (A, B) = 1, A < B); sequence gives values of B, sorted.
Any term in this sequence is given by f(m,n) = 2*m*n or g(m,n) = m^2  n^2 where m and n are any two positive integers, m > 1, n < m, the greatest common divisor of m and n is 1, m and n are not both odd; e.g., f(m,n) = f(2,1) = 2*2*1 = 4.  Agola Kisira Odero, Apr 29 2016
All terms are composite.  Thomas Ordowski, Mar 12 2017
a(1) is the only power of 2.  Torlach Rush, Nov 08 2019
The first term appearing twice is 420 = a(75) = a(76) = A024410(1).  Giovanni Resta, Nov 11 2019


LINKS

Giovanni Resta, Table of n, a(n) for n = 1..10000
Ron Knott, Pythagorean Triples and Online Calculators


CROSSREFS

Cf. A020882, A020884, A020885, A020886, A024354, A024410.
Sequence in context: A215011 A024353 A024354 * A002365 A212245 A046087
Adjacent sequences: A020880 A020881 A020882 * A020884 A020885 A020886


KEYWORD

nonn


AUTHOR

Clark Kimberling


EXTENSIONS

Extended and corrected by David W. Wilson


STATUS

approved



