The sequence defined by a0=1a_0 = 1a0=1 and an=n⋅an−1a_n = n \cdot a_{n-1}an=n⋅an−1 for n≥1n \geq 1n≥1 represents which well-known function?
an=n!a_n = n!an=n!
an=2na_n = 2^nan=2n
an=Fna_n = F_nan=Fn (Fibonacci)
an=Cna_n = C_nan=Cn (Catalan numbers)