public static void main ( String [ ] args ) {
  Scanner sc = new Scanner ( System . in ) ;
  int n = sc . nextInt ( ) ;
  int k = sc . nextInt ( ) ;
  double [ ] [ ] dp = new double [ 1001 ] [ 1001 ] ;
  for ( int r = n - 1 ;
  r > 0 ;
  r -- ) {
    dp [ r ] [ 0 ] = dp [ r + 1 ] [ 0 ] ;
    for ( int s = 1 ;
    s <= k ;
    s ++ ) {
      dp [ r ] [ s ] = dp [ r + 1 ] [ s ] + Math . max ( 1.0 / n + dp [ r + 1 ] [ s - 1 ] , dp [ r + 1 ] [ s ] ) / r ;
    }
  }
  System . out . println ( Math . max ( 1.0 / n + dp [ 1 ] [ k - 1 ] , dp [ 1 ] [ k ] ) ) ;
}

public static void main ( String [ ] args ) { Scanner sc = new Scanner ( System . in ) ; int n = sc . nextInt ( ) ; int k = sc . nextInt ( ) ; double [ ] [ ] dp = new double [ 1001 ] [ 1001 ] ; for ( int r = n - 1 ; r > 0 ; r -- ) { dp [ r ] [ 0 ] = dp [ r + 1 ] [ 0 ] ; for ( int s = 1 ; s <= k ; s ++ ) { dp [ r ] [ s ] = dp [ r + 1 ] [ s ] + Math . max ( 1.0 / n + dp [ r + 1 ] [ s - 1 ] , dp [ r + 1 ] [ s ] ) / r ; } } System . out . println ( Math . max ( 1.0 / n + dp [ 1 ] [ k - 1 ] , dp [ 1 ] [ k ] ) ) ; }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (array_type element: (type_identifier) dimensions: (dimensions)) name: (identifier))) body: (block (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (type_identifier) arguments: (argument_list (field_access object: (identifier) field: (identifier)))))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (local_variable_declaration type: (array_type element: (floating_point_type) dimensions: (dimensions)) declarator: (variable_declarator name: (identifier) value: (array_creation_expression type: (floating_point_type) dimensions: (dimensions_expr (decimal_integer_literal)) dimensions: (dimensions_expr (decimal_integer_literal))))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (identifier) right: (decimal_integer_literal)))) condition: (binary_expression left: (identifier) right: (decimal_integer_literal)) update: (update_expression (identifier)) body: (block (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (decimal_integer_literal)) right: (array_access array: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) index: (decimal_integer_literal)))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (identifier)) update: (update_expression (identifier)) body: (block (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (identifier)) right: (binary_expression left: (array_access array: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) index: (identifier)) right: (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (binary_expression left: (decimal_floating_point_literal) right: (identifier)) right: (array_access array: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) index: (binary_expression left: (identifier) right: (decimal_integer_literal)))) (array_access array: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) index: (identifier)))) right: (identifier))))))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (binary_expression left: (decimal_floating_point_literal) right: (identifier)) right: (array_access array: (array_access array: (identifier) index: (decimal_integer_literal)) index: (binary_expression left: (identifier) right: (decimal_integer_literal)))) (array_access array: (array_access array: (identifier) index: (decimal_integer_literal)) index: (identifier)))))))))