OFFSET
1,1
COMMENTS
These numbers are almost always divisible by 7. 85 in the example is an exception and so is 184.
EXAMPLE
x=85,y=204, 85^2+204^2 = 221^2
PROG
(PARI) xydivxpy2(n) = { for(x=1, n, for(y=x, n, h=x*y/(x+y); if(h==floor(h), z = sqrt (x^2+y^2); if(z==floor(z), print1(x", ") ) ) ) ) }
CROSSREFS
KEYWORD
nonn
AUTHOR
Cino Hilliard, Dec 02 2003, corrected Nov 23 2006
STATUS
approved