public static int pell ( int n ) {
  if ( n <= 2 ) return n ;
  return 2 * pell ( n - 1 ) + pell ( n - 2 ) ;
}

public static int pell ( int n ) { if ( n <= 2 ) return n ; return 2 * pell ( n - 1 ) + pell ( n - 2 ) ; }
(method_declaration (modifiers) type: (integral_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (integral_type) name: (identifier))) body: (block (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal))) consequence: (return_statement (identifier))) (return_statement (binary_expression left: (binary_expression left: (decimal_integer_literal) right: (method_invocation name: (identifier) arguments: (argument_list (binary_expression left: (identifier) right: (decimal_integer_literal))))) right: (method_invocation name: (identifier) arguments: (argument_list (binary_expression left: (identifier) right: (decimal_integer_literal))))))))