Last non-zero

From this link , we have If $D(N)$ denotes the last non zero digit of factorial, then

$D(N)=4D\left(\left\lfloor{\frac N5}\right\rfloor\right)\cdot D(\mbox{Units digit of \$N\$}) \qquad \mbox{(If tens digit of \$N\$ is odd)}$ $D(N)=6D\left(\left\lfloor{\frac N5}\right\rfloor\right)\cdot D(\mbox{Units digit of \$N\$}) \qquad \mbox{(If tens digit of \$N\$ is even)}$

Where $\left\lfloor\cdots\right\rfloor$ is greatest integer function.

This can be coded in python 3.4 like this:

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Dsmall = [1, 1, 2, 6, 4, 2, 2, 4, 2 , 8]

def D(n):
    "Last non-zero"
    if n < 10:
        return Dsmall[n]
    elif (n//10)%2 == 0:
        return (4*D(int(n/5))*Dsmall[n%10])%10
    else:
        return (6*D(int(n/5))*Dsmall[n%10])%10

print(D(2015))