game_of_ur

//
// Game of Ur
//

var roll = function() {
	return flip() + flip() + flip() + flip();
}

var game = function() {
	var n = sample(RandomInteger({n: 20}));
	var s = sum(repeat(n, roll))
	condition(s === 13);
	return n
}

var dist = Infer(game);
viz(dist);