def test_issue_8496():
n = Symbol("n")
k = Symbol("k")
pytest.raises(TypeError, lambda: catalan(n, k))
pytest.raises(TypeError, lambda: euler(n, k))
def test_euler_failing():
# depends on dummy variables being implemented https://github.com/sympy/sympy/issues/5665
assert euler(2 * n).rewrite(Sum) == I * Sum(
Sum((-1)**_j * 2**(-_k) * I**(-_k) *
(-2 * _j + _k)**(2 * n + 1) * binomial(_k, _j) / _k, (_j, 0, _k)),
(_k, 1, 2 * n + 1))
def test_sympyissue_8496():
n = Symbol("n")
k = Symbol("k")
pytest.raises(TypeError, lambda: catalan(n, k))
pytest.raises(TypeError, lambda: euler(n, k))
def test_euler():
assert euler(0) == 1
assert euler(1) == 0
assert euler(2) == -1
assert euler(3) == 0
assert euler(4) == 5
assert euler(6) == -61
assert euler(8) == 1385
assert euler(20, evaluate=False) != 370371188237525
n = Symbol('n', integer=True)
assert euler(n) != -1
assert euler(n).subs(n, 2) == -1
assert euler(20).evalf() == 370371188237525.0
assert euler(20, evaluate=False).evalf() == 370371188237525.0
assert euler(n).rewrite(Sum) == euler(n)
# XXX: Not sure what the guy who wrote this test was trying to do with the _j and _k stuff
assert euler(2 * n + 1).rewrite(Sum) == 0
def test_euler():
assert euler(0) == 1
assert euler(1) == 0
assert euler(2) == -1
assert euler(3) == 0
assert euler(4) == 5
assert euler(6) == -61
assert euler(8) == 1385
assert euler(20, evaluate=False) != 370371188237525
n = Symbol('n', integer=True)
assert euler(n) != -1
assert euler(n).subs({n: 2}) == -1
assert euler(20).evalf() == 370371188237525.0
assert euler(20, evaluate=False).evalf() == 370371188237525.0
assert euler(Rational(1, 2)).evalf() == euler(Rational(1, 2))
assert euler(n).rewrite(Sum) == euler(n)
# XXX: Not sure what the guy who wrote this test was trying to do with the _j and _k stuff
assert euler(2*n + 1).rewrite(Sum) == 0