I was fooling around with sparse representation of K_n (tridiagonal -1 2 -1)
which theoretically has a determinant of n+1. I ran across this old post.
Both SuperLU and CHOLMOD don't seem to have the precision to get the correct determinant once you get above n=1e6.
from scipy.sparse import diags
from scipy.sparse.linalg import splu
from sksparse.cholmod ...