#include <stdio.h>
#include <stdlib.h>

#define MAX_SIZE 48

/* STL ちゃんと覚えよう。と思った今日この頃 */
void init(int *single_prime_powered) {
	int i, j, k, p;
	int primes[MAX_SIZE], size;
	
	size = 0;
	for(i = 2; i < MAX_SIZE; ++i) {
		for(j = 0; j < size; ++j) {
			if( i % primes[j] == 0 ) break;
		}
		if( j == size ) primes[size++] = i;
	}
	
	single_prime_powered[0] = 0;
	single_prime_powered[1] = 0;
	for(i = 2; i < MAX_SIZE; ++i) {
		single_prime_powered[i] = 0;
		for(j = 0; j < size; ++j) {
			p = primes[j];
			for(k = i; k > 1; k /= p) {
				if( k % p != 0 ) break;
			}
			if( k == 1 ) {
				single_prime_powered[i] = p;
				break;
			}
		}
	}
}

long long mul(int *a, int size) {
	int i;
	long long result = 1;
	for(i = 0; i < size; ++i) {
		result *= a[i];
	}
	return result;
}

long long solve(long long n, int d) {
	int result;
	for(result = 1; result < d; ++result) {
		if( (result * n) % d == 1 ) break;
	}
	return result;
}

int main() {
	int n, i, p, d;
	int used[MAX_SIZE], input[MAX_SIZE];
	int single_prime_powered[MAX_SIZE];
	int used_number[MAX_SIZE], size;
	long long lcm, result;

	init(single_prime_powered);

	while(1) {
		scanf("%d", &n);
		if( n == 0 ) break;

		for(i = 1; i <= n; ++i) {
			scanf("%d", &input[i]);
			used[i] = 0;
		}
		
		size = 0;
		for(i = n; i > 0; --i) {
			p = single_prime_powered[i];
			if( p && !used[p] ) {
				used[p] = 1;
				used_number[size++] = i;
			}
		}
		
		lcm = mul(used_number, size);
		result = 0;
		for(i = 0; i < size; ++i) {
			d = used_number[i];
			result += (lcm / d) * solve(lcm / d, d) * input[d] % lcm; /* d > solve(lcm/d, d) */
			result %= lcm;
		}
		printf("%lld\n", result);
	}
	return 0;
}