#include<stdio.h>
int main(){
	int v[801],n,s,i,j,k;
	freopen("nrtri.in","r",stdin);
	freopen("nrtri.out","w",stdout);
	scanf("%d",&n);
	for (i=1;i<n+1;++i)
		scanf("%d ",&v[i]);
	s=0;
	for (i=1;i<n+1;++i)
		for (j=1;j<n+1;++j)
			for (k=1;k<n+1;++k){
				if(i==j) || (i==k) || (j==k){
				}
				else {
					if(v[i]+v[j]>=v[k])&&(v[i]+v[k]>=v[j])&&(v[k]+v[j]>=v[i])
						s=s+1;
				}
			}
	s=s/3;
	printf("%d\n",s);
	fclose(stdin);
	fclose(stdout);
	return 0;
}