Sum of squares of binomial coefficients | function to return product of number from start to end . ; Return the sum of square of binomial coefficient ; Driver Code
< ? php function factorial ( $ start , $ end ) { $ res = 1 ; for ( $ i = $ start ; $ i <= $ end ; $ i ++ ) $ res *= $ i ; return $ res ; } function sumofsquare ( $ n ) { return factorial ( $ n + 1 , 2 * $ n ) / factorial ( 1 , $ n ) ; } $ n = 4 ; echo sumofsquare ( $ n ) , " STRNEWLINE " ; ? >