#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
const int mx=1000000;
const int mod=998244353;
const int inv2=(mod+1)/2;
#define N 1000100
inline int read(){
	int x=0,f=1;
	char c=getchar();
	while(c<'0'||c>'9'){
		if(c=='-')f=-1;
		c=getchar();
	}
	while(c>='0'&&c<='9'){
		x=(x<<1)+(x<<3)+c-'0';
		c=getchar();
	}
	return x*f;
}
int n,mu[N],s[N],c[N],ans;
void init(int n){
	mu[1]=1;
	for(int i=1;i<=n;++i){
		for(int j=i+i;j<=n;j+=i){
			mu[j]-=mu[i];
		}
	}
	for(int i=1;i<=n;++i){
		for(int j=i;j<=n;j+=i){
			s[j]=(s[j]+mu[i]*i)%mod;
		}
	}
}
int main(){
	n=read();
	for(int i=1;i<=n;++i){
		++c[read()];
	}
	init(mx);
	for(int i=1;i<=mx;++i){
		int tmp=0;
		for(int j=1;j<=mx/i;++j){
			tmp=(tmp+1LL*j*c[j*i])%mod;
		}
		tmp=1LL*tmp*tmp%mod*i%mod*s[i]%mod;
		ans=(ans+tmp)%mod;
	}
	for(int i=1;i<=mx;++i){
		ans=(ans-1LL*c[i]*i)%mod;
	}
	ans=1LL*(ans+mod)%mod*inv2%mod;
	printf("%d\n",ans);
	return 0;
}

