Find the sum of all Betrothed numbers up to N | Java program to find the sum of the all betrothed numbers up to N ; Function to find the sum of the all betrothed numbers ; To store the betrothed numbers ; Calculate sum of number_1 's divisors   1 is always a divisor ; i = 2 because we don 't   want to include   1 as a divisor.  ; Sum all betrothed numbers up to N ; Driver code
import java . util . * ; class GFG { public static int Betrothed_Sum ( int n ) { Vector < Integer > Set = new Vector < Integer > ( ) ; for ( int number_1 = 1 ; number_1 < n ; number_1 ++ ) { int sum_divisor_1 = 1 ; int i = 2 ; while ( i * i <= number_1 ) { if ( number_1 % i == 0 ) { sum_divisor_1 = sum_divisor_1 + i ; if ( i * i != number_1 ) sum_divisor_1 += number_1 / i ; } i ++ ; } if ( sum_divisor_1 > number_1 ) { int number_2 = sum_divisor_1 - 1 ; int sum_divisor_2 = 1 ; int j = 2 ; while ( j * j <= number_2 ) { if ( number_2 % j == 0 ) { sum_divisor_2 += j ; if ( j * j != number_2 ) sum_divisor_2 += number_2 / j ; } j = j + 1 ; } if ( sum_divisor_2 == number_1 + 1 && number_1 <= n && number_2 <= n ) { Set . add ( number_1 ) ; Set . add ( number_2 ) ; } } } int Summ = 0 ; for ( int i = 0 ; i < Set . size ( ) ; i ++ ) { if ( Set . get ( i ) <= n ) Summ += Set . get ( i ) ; } return Summ ; } public static void main ( String [ ] args ) { int n = 78 ; System . out . println ( Betrothed_Sum ( n ) ) ; } }