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#include <stdio.h>

/* Time: 2m5.335s */

typedef struct
{
	int p;
	int np;
} prime_factor;

/* factorize n, return number of prime factors */
int get_prime_factors(int n, prime_factor *pf)
{
	int npf = 0;
	int np;
	if (n <= 1)
		return 0;
	if (n % 2 == 0) {
		pf[0].p = 2;
		np = 0;
		while (n % 2 == 0) {
			n /= 2;
			np++;
		}
		pf[0].np = np;
		npf = 1;
	}
	for (int i = 3; i * i <= n; i += 2) {
		if (n % i == 0) {
			pf[npf].p = i;
			np = 0;
			while (n % i == 0) {
				n /= i;
				np ++;
			}
			pf[npf].np = np;
			npf++;
		}
	}
	if (n > 1) {
		pf[npf].p = n;
		pf[npf].np = 1;
		npf++;
	}
	return npf;
}

int get_factors_from_pf(prime_factor pf[], int npf, int factors[])
{
	factors[0] = 1;
	int idx = 1;
	for (int i = 0; i < npf; i++) {
		int nidx = idx;
		for (int j = 0; j < pf[i].np; j++) {
			for (int k = 0; k < idx; k++) {
				factors[nidx+k] = factors[nidx+k-idx] * pf[i].p;
			}
			nidx += idx;
		}
		idx = nidx;
	}
	return idx;
}

int get_all_factors(int n, int factors[])
{
	prime_factor pf[100];
	int npf = get_prime_factors(n, pf);

	return get_factors_from_pf(pf, npf, factors);
}

int isprime(int n)
{
	if (n < 2 || n % 2 == 0)
		return 0;

	for (int i = 3; i * i <= n; i += 2) {
		if (n % i == 0)
			return 0;
	}

	return 1;
}

int main()
{
	long long sum = 3; /* n can be 1, 2 */
	int factors[10000];
	prime_factor pf[100];

	for (int i = 6; i <= 100000000; i += 4) { /* n must be 4k+2 */
		int isok = 1;
		int npf = get_prime_factors(i, pf);
		for (int j = 0; j < npf; j++) {
			if (pf[j].np > 1) {
				isok = 0;
				break;
			}
		}
		if (!isok)
			continue;

		int nf = get_factors_from_pf(pf, npf, factors);
		for (int j = 0; j < nf; j++) {
			int t = factors[j] + i/factors[j];
			if (!isprime(t)) {
				isok = 0;
				break;
			}
		}
		if (isok) {
			sum += i;
		}
	}
	printf("%lld\n", sum);
}