def _eval_rewrite_as_gamma(self,n):
# The gamma function allows to generalize Catalan numbers to complex n
return 4**n*C.gamma(n + S.Half)/(C.gamma(S.Half)*C.gamma(n+2))
def _eval_rewrite_as_gamma(self, n):
# The gamma function allows to generalize Catalan numbers to complex n
return 4**n * C.gamma(n + S.Half) / (C.gamma(S.Half) * C.gamma(n + 2))
def eval(cls, n, evaluate=True):
if n.is_Integer and n.is_nonnegative:
return 4**n*C.gamma(n + S.Half)/(C.gamma(S.Half)*C.gamma(n+2))
def eval(cls, n, evaluate=True):
if n.is_Integer and n.is_nonnegative:
return 4**n * C.gamma(n + S.Half) / (C.gamma(S.Half) *
C.gamma(n + 2))
