#include<bits/stdc++.h>

typedef long long LL;

const int N=1000005;
const int MOD=998244353;

int n,s[N],t[N],prime[N],tot,mu[N],mx,ny[N];
bool not_prime[N];

void get_prime(int n)
{
	mu[1]=1;
	for (int i=2;i<=n;i++)
	{
		if (!not_prime[i]) prime[++tot]=i,mu[i]=-1;
		for (int j=1;j<=tot&&i*prime[j]<=n;j++)
		{
			not_prime[i*prime[j]]=1;
			if (i%prime[j]==0) break;
			mu[i*prime[j]]=-mu[i];
		}
	}
}

int main()
{
	scanf("%d",&n);
	for (int i=1,x;i<=n;i++) scanf("%d",&x),mx=std::max(mx,x),s[x]++;
	get_prime(mx);
	ny[0]=ny[1]=1;
	for (int i=2;i<=mx;i++) ny[i]=(LL)(MOD-MOD/i)*ny[MOD%i]%MOD;
	for (int i=1;i<=mx;i++)
	{
		int sum=0;
		for (int j=i;j<=mx;j+=i)
		{
			(t[i]+=(LL)sum*j%MOD*s[j]%MOD)%=MOD;
			(t[i]+=(LL)s[j]*(s[j]-1)/2%MOD*j%MOD*j%MOD)%=MOD;
			(sum+=(LL)j*s[j]%MOD)%=MOD;
		}
	}
	int ans=0;
	for (int i=1;i<=mx;i++)
		for (int j=i;j<=mx;j+=i)
			(ans+=(LL)mu[j/i]*t[j]*ny[i]%MOD)%=MOD;
	printf("%d\n",(ans+MOD)%MOD);
	return 0;
}