#include<bits/stdc++.h>

using namespace std;

typedef long long LL;
#define N 1200000

const LL mod=998244353;
LL n,m,x,ans,mu[N],pr[N],vis[N],tot,f[N],g[N];

void upd(LL &x,LL y){
	x=(x+y)%mod;
}

int main(){
	n=1000000;
	mu[1]=1; pr[1]=0;
	for (LL i=2;i<=n;++i){
		if (!vis[i]){
			pr[++tot]=i;
			mu[i]=-1;
		}
		for (LL j=1;j<=tot;++j)
			if (i*pr[j]<=n){
				vis[i*pr[j]]=pr[j];
				if (i%pr[j]==0){
					mu[i*pr[j]]=0;
					break;
				}
				mu[i*pr[j]]=-mu[i];
			}
			else break;
	}
	for (LL i=1;i<=n;++i) if (mu[i])
		for (LL j=1;i*j<=n;++j)
			upd(f[i*j],mu[i]*i*i%mod*j);
	scanf("%lld",&m);
	for (LL i=1;i<=m;++i){
		scanf("%lld",&x);
		upd(ans,-x);
		++g[x];
	}
	for (LL i=1;i<=n;++i){
		LL tmp=0;
		for (LL j=1;i*j<=n;++j)
			upd(tmp,j*g[i*j]);
		upd(ans,f[i]*tmp%mod*tmp);
	}
	ans=(ans*((mod+1)/2)%mod+mod)%mod;
	printf("%lld\n",ans);
	
	return 0;
}
			