#include<cstdio>
int n, i, j, k, nr, a[10000];

int main()
{ 
  freopen("nrtri.in", "r", stdin);
  freopen("nrtri.out", "w", stdout);
  
  scanf("%d", &n);
  for(i=1; i<=n; ++i) scanf("%d ", &a[i]);

  for(i=1; i<n-1; ++i)
	  for(j=2; j<n; ++j) 
		  for(k=3; k<=n; ++k) if(a[i]>a[j] && a[i]>a[k] && a[i]<a[j]+a[k]) ++nr;
                              else if(a[j]>a[k] && a[j]>a[i] && a[j]<a[i]+a[k]) ++nr;
                                   else if(a[k]>a[i] && a[k]>a[j] && a[k]<a[i]+a[j]) ++nr;		  
  printf("%d ", nr);
  fclose(stdin);
  fclose(stdout);
  return 0;
}