public String getRandomSequence(int length) {
		StringBuilder builder = new StringBuilder();
		for (int i = 0; i < length; ++i) {
			double rand = Math.random();
			if (rand > 0.75) {
				builder.append("C");
			} else if (rand > 0.5) {
				builder.append("G");
			} else if (rand > 0.25) {
				builder.append("T");
			} else {
				builder.append("A");
			}
		}
		return builder.toString();
	}