#include<bits/stdc++.h>
#define int __int128
#define ldb long double
using namespace std;
typedef pair<int,int> PII;
inline int read(){
	int x=0,f=1;char ch;
	while(!isdigit(ch=getchar()))if(ch=='-')f=-f;
	do x=(x<<3)+(x<<1)+(ch^48);while(isdigit(ch=getchar()));
	return x*f;
}
int ptop,pstk[40];
inline void write(int x,char ch='\n'){
	if(!x){
        putchar('0'),putchar(ch);
        return;
	}
	if(x<0)putchar('-'),x=-x;
	while(x)pstk[ptop++]=x%10,x/=10;
	while(ptop)putchar(pstk[--ptop]+'0');
	putchar(ch);
}
const int N=1e6+5,INF=1e36;
int n,k,tot;
int a[N],b[N],c[N],s[N],g[N],ans[N];
inline int gcd(int x,int y){
	return y?gcd(y,x%y):x;
}
void MAIN(){
	n=read(),read(),k=read();
    for(int i=1;i<=n;++i)a[i]=read();
    sort(a+1,a+n+1);
    int m=0,q=0;
    for(int i=1;i<=n;++i)
        if(i>1&&a[i]==a[i-1])b[++m]=a[i];
        else c[++q]=a[i];
    n=q;
    for(int i=1;i<=n;++i)
        a[i]=c[i],
        g[i]=gcd(g[i-1],a[i]),
        s[i]=s[i-1]+a[i];
    for(int i=0;i<=k;++i)ans[i]=-INF;
    for(int l=1,r=0;l<=n;l=r+1){
        int mx=-INF;
        for(r=l;r<=n&&g[r]==g[l];++r);
        --r;
		for(int i=r+1;i<=n;++i)
			a[i]=gcd(a[i],g[l]),
			mx=max(mx,a[i]-c[i]);
		for(int i=r;i>=l;--i)
			ans[i]=s[n]-s[i]+mx,
			a[i]=gcd(a[i],g[l]),
			mx=max(mx,a[i]-c[i]);
    }
	for(int i=1;i<=m;++i)b[i]+=b[i-1];
	tot=-INF;
	if(k<=m)tot=s[n]+b[m]-b[k];
	for(int i=0;i<=m&&i<=k;++i)
		tot=max(tot,b[m]-b[i]+ans[k-i]);
	write(tot);
}
signed main(){
	for(int T=1;T--;MAIN());
    return 0;
}
/*

*/