OFFSET
1,8
COMMENTS
Conjecture: the only solutions for x!+y!=n^2 (x <= y) are x=0,0,0,1,1,1,2,4 and y=4,5,7,4,5,7,2,5 respectively.
PROG
(PARI) sumfactsq(n) = { for(x=0, n, for(y=1, n, z = x!+y!; if(issquare(z), print1(x" ")) ) ) }
CROSSREFS
KEYWORD
nonn
AUTHOR
Cino Hilliard, May 25 2003
EXTENSIONS
Edited and corrected by Farideh Firoozbakht, Jul 07 2009
STATUS
approved