[Python] Sympy rsolve function returns wrong results

I have the following recurrence relation:

an = 0.996 · an–1 + 0.004 · an–10 + 0.04

with initial conditions: an = 0 for all n ≤ 9.

Code:

import sympy as sp

n = sp.symbols('n')
y = sp.Function('y')
recurrence = sp.rsolve(
y(n) - sp.Rational(0.996) * y(n-1) - sp.Rational(0.004) * y(n-10) - sp.Rational(0.04),
y(n),
{
y(0): 0,
y(1): 0,
y(2): 0,
y(3): 0,
y(4): 0,
y(5): 0,
y(6): 0,
y(7): 0,
y(8): 0,
y(9): 0,
}
)


The wrong result I get is just a constant number. Why do I not get an expression that depends on the variable n?

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