1, 3, 7, 19, 51, 135, 361, 963, 2570, 6859, 18303, 48839, 130321, 347749, 927933, 2476099, 6607227, 17630734, 47045881, 125537306, 334983955, 893871739, 2385208822, 6364695153, 16983563041, 45318967620, 120929207915, 322687697779, 861060384776, 2297654950385