static int numberSequence ( int n ) {
  int num = ( int ) ( Math . pow ( 4 , n ) - Math . pow ( 2 , n ) ) - 1 ;
  return num ;
}

static int numberSequence ( int n ) { int num = ( int ) ( Math . pow ( 4 , n ) - Math . pow ( 2 , n ) ) - 1 ; return num ; }
(method_declaration (modifiers) type: (integral_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (integral_type) name: (identifier))) body: (block (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (cast_expression type: (integral_type) value: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal) (identifier))) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal) (identifier)))))) right: (decimal_integer_literal)))) (return_statement (identifier))))