function to check if there exist two numbers sum of whose squares is n .
< ? php function sumSquare ( int $ n ) { for ( $ i = 1 ; $ i * $ i <= $ n ; $ i ++ ) for ( $ j = 1 ; $ j * $ j <= $ n ; $ j ++ ) if ( $ i * $ i + $ j * $ j == $ n ) { echo $ i , " ^ 2 ▁ + ▁ " , $ j , " ^ 2" ; return true ; } return false ; }