import java.util.*;
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int n = in.nextInt();
int[][] arr = new int[7][7];
int[] count = new int[7];
for (int i = 0; i < n; i++) {
int tmp = in.nextInt();
int yu = tmp % 7;
arr[yu][getTens(tmp) % 7]++;
count[yu]++;
}
int result = 0;
for (int i = 0; i < 7; i++) {
for (int j = 1; j < 7; j++) {
if(arr[i][j] == 0) {
continue;
}
for (int k = 0; k < 7; k++) {
if((i + j * k) % 7 == 0) {
int sum = count[k];
if(k == i) {
sum--;
}
result += arr[i][j] * sum;
}
}
}
}
System.out.println(result);
}
private static int getTens(int num) {
int sum = 1;
while ((num /= 10) != 0) {
sum++;
}
return (int) Math.pow(3, sum);
}
}
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