OFFSET
1,1
COMMENTS
a(23) = 14280 is the first perimeter of 3 primitive Pythagorean triangles: {119, 7080, 7081}, {168, 7055, 7057} and {3255, 5032, 5993}. - Jean-François Alcover, Mar 14 2012
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10000
Leon Bernstein, Primitive Pythagorean Triples, The Fibonacci Quarterly 20.3 (1982) 227-241.
Ron Knott, Pythagorean Triples and Online Calculators
Lindsay Witcosky, Perimeters of primitive Pythagorean triangles
EXAMPLE
a(1) = 1716 with precisely two primitive Pythagorean triangles (with increasing entries): {195, 748, 773} and {364, 627, 725}. From Ron Knott's link. This is the first example of the family of perimeters 12*b(k)*(b(k) + 2) with b(k) = A007528(k), for k >= 2. See the Bernstein link, p. 234, Theorem 5. a). - Wolfdieter Lang, Sep 24 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved