def __init__(self): r""" TESTS:: sage: from sage.combinat.backtrack import PositiveIntegerSemigroup sage: PP = PositiveIntegerSemigroup() """ SearchForest.__init__(self, facade = ZZ, category=(InfiniteEnumeratedSets(), CommutativeAdditiveSemigroups(), Monoids()))
def super_categories(self): """ EXAMPLES:: sage: CommutativeAdditiveMonoids().super_categories() [Category of commutative additive semigroups] """ return [CommutativeAdditiveSemigroups()]