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

#define TRY_MAX 40000000L

/* keep a list of small primes to sieve with */
#define PSIZE 1000
int small_p[PSIZE] = {
    2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61,
    67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137,
    139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211,
    223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283,
    293, 307, 311, 313, 317, 331, 337, 347, 349, 353, 359, 367, 373, 379,
    383, 389, 397, 401, 409, 419, 421, 431, 433, 439, 443, 449, 457, 461,
    463, 467, 479, 487, 491, 499, 503, 509, 521, 523, 541, 547, 557, 563,
    569, 571, 577, 587, 593, 599, 601, 607, 613, 617, 619, 631, 641, 643,
    647, 653, 659, 661, 673, 677, 683, 691, 701, 709, 719, 727, 733, 739,
    743, 751, 757, 761, 769, 773, 787, 797, 809, 811, 821, 823, 827, 829,
    839, 853, 857, 859, 863, 877, 881, 883, 887, 907, 911, 919, 929, 937,
    941, 947, 953, 967, 971, 977, 983, 991, 997, 1009, 1013, 1019, 1021,
    1031, 1033, 1039, 1049, 1051, 1061, 1063, 1069, 1087, 1091, 1093,
    1097, 1103, 1109, 1117, 1123, 1129, 1151, 1153, 1163, 1171, 1181,
    1187, 1193, 1201, 1213, 1217, 1223, 1229, 1231, 1237, 1249, 1259,
    1277, 1279, 1283, 1289, 1291, 1297, 1301, 1303, 1307, 1319, 1321,
    1327, 1361, 1367, 1373, 1381, 1399, 1409, 1423, 1427, 1429, 1433,
    1439, 1447, 1451, 1453, 1459, 1471, 1481, 1483, 1487, 1489, 1493,
    1499, 1511, 1523, 1531, 1543, 1549, 1553, 1559, 1567, 1571, 1579,
    1583, 1597, 1601, 1607, 1609, 1613, 1619, 1621, 1627, 1637, 1657,
    1663, 1667, 1669, 1693, 1697, 1699, 1709, 1721, 1723, 1733, 1741,
    1747, 1753, 1759, 1777, 1783, 1787, 1789, 1801, 1811, 1823, 1831,
    1847, 1861, 1867, 1871, 1873, 1877, 1879, 1889, 1901, 1907, 1913,
    1931, 1933, 1949, 1951, 1973, 1979, 1987, 1993, 1997, 1999, 2003,
    2011, 2017, 2027, 2029, 2039, 2053, 2063, 2069, 2081, 2083, 2087,
    2089, 2099, 2111, 2113, 2129, 2131, 2137, 2141, 2143, 2153, 2161,
    2179, 2203, 2207, 2213, 2221, 2237, 2239, 2243, 2251, 2267, 2269,
    2273, 2281, 2287, 2293, 2297, 2309, 2311, 2333, 2339, 2341, 2347,
    2351, 2357, 2371, 2377, 2381, 2383, 2389, 2393, 2399, 2411, 2417,
    2423, 2437, 2441, 2447, 2459, 2467, 2473, 2477, 2503, 2521, 2531,
    2539, 2543, 2549, 2551, 2557, 2579, 2591, 2593, 2609, 2617, 2621,
    2633, 2647, 2657, 2659, 2663, 2671, 2677, 2683, 2687, 2689, 2693,
    2699, 2707, 2711, 2713, 2719, 2729, 2731, 2741, 2749, 2753, 2767,
    2777, 2789, 2791, 2797, 2801, 2803, 2819, 2833, 2837, 2843, 2851,
    2857, 2861, 2879, 2887, 2897, 2903, 2909, 2917, 2927, 2939, 2953,
    2957, 2963, 2969, 2971, 2999, 3001, 3011, 3019, 3023, 3037, 3041,
    3049, 3061, 3067, 3079, 3083, 3089, 3109, 3119, 3121, 3137, 3163,
    3167, 3169, 3181, 3187, 3191, 3203, 3209, 3217, 3221, 3229, 3251,
    3253, 3257, 3259, 3271, 3299, 3301, 3307, 3313, 3319, 3323, 3329,
    3331, 3343, 3347, 3359, 3361, 3371, 3373, 3389, 3391, 3407, 3413,
    3433, 3449, 3457, 3461, 3463, 3467, 3469, 3491, 3499, 3511, 3517,
    3527, 3529, 3533, 3539, 3541, 3547, 3557, 3559, 3571, 3581, 3583,
    3593, 3607, 3613, 3617, 3623, 3631, 3637, 3643, 3659, 3671, 3673,
    3677, 3691, 3697, 3701, 3709, 3719, 3727, 3733, 3739, 3761, 3767,
    3769, 3779, 3793, 3797, 3803, 3821, 3823, 3833, 3847, 3851, 3853,
    3863, 3877, 3881, 3889, 3907, 3911, 3917, 3919, 3923, 3929, 3931,
    3943, 3947, 3967, 3989, 4001, 4003, 4007, 4013, 4019, 4021, 4027,
    4049, 4051, 4057, 4073, 4079, 4091, 4093, 4099, 4111, 4127, 4129,
    4133, 4139, 4153, 4157, 4159, 4177, 4201, 4211, 4217, 4219, 4229,
    4231, 4241, 4243, 4253, 4259, 4261, 4271, 4273, 4283, 4289, 4297,
    4327, 4337, 4339, 4349, 4357, 4363, 4373, 4391, 4397, 4409, 4421,
    4423, 4441, 4447, 4451, 4457, 4463, 4481, 4483, 4493, 4507, 4513,
    4517, 4519, 4523, 4547, 4549, 4561, 4567, 4583, 4591, 4597, 4603,
    4621, 4637, 4639, 4643, 4649, 4651, 4657, 4663, 4673, 4679, 4691,
    4703, 4721, 4723, 4729, 4733, 4751, 4759, 4783, 4787, 4789, 4793,
    4799, 4801, 4813, 4817, 4831, 4861, 4871, 4877, 4889, 4903, 4909,
    4919, 4931, 4933, 4937, 4943, 4951, 4957, 4967, 4969, 4973, 4987,
    4993, 4999, 5003, 5009, 5011, 5021, 5023, 5039, 5051, 5059, 5077,
    5081, 5087, 5099, 5101, 5107, 5113, 5119, 5147, 5153, 5167, 5171,
    5179, 5189, 5197, 5209, 5227, 5231, 5233, 5237, 5261, 5273, 5279,
    5281, 5297, 5303, 5309, 5323, 5333, 5347, 5351, 5381, 5387, 5393,
    5399, 5407, 5413, 5417, 5419, 5431, 5437, 5441, 5443, 5449, 5471,
    5477, 5479, 5483, 5501, 5503, 5507, 5519, 5521, 5527, 5531, 5557,
    5563, 5569, 5573, 5581, 5591, 5623, 5639, 5641, 5647, 5651, 5653,
    5657, 5659, 5669, 5683, 5689, 5693, 5701, 5711, 5717, 5737, 5741,
    5743, 5749, 5779, 5783, 5791, 5801, 5807, 5813, 5821, 5827, 5839,
    5843, 5849, 5851, 5857, 5861, 5867, 5869, 5879, 5881, 5897, 5903,
    5923, 5927, 5939, 5953, 5981, 5987, 6007, 6011, 6029, 6037, 6043,
    6047, 6053, 6067, 6073, 6079, 6089, 6091, 6101, 6113, 6121, 6131,
    6133, 6143, 6151, 6163, 6173, 6197, 6199, 6203, 6211, 6217, 6221,
    6229, 6247, 6257, 6263, 6269, 6271, 6277, 6287, 6299, 6301, 6311,
    6317, 6323, 6329, 6337, 6343, 6353, 6359, 6361, 6367, 6373, 6379,
    6389, 6397, 6421, 6427, 6449, 6451, 6469, 6473, 6481, 6491, 6521,
    6529, 6547, 6551, 6553, 6563, 6569, 6571, 6577, 6581, 6599, 6607,
    6619, 6637, 6653, 6659, 6661, 6673, 6679, 6689, 6691, 6701, 6703,
    6709, 6719, 6733, 6737, 6761, 6763, 6779, 6781, 6791, 6793, 6803,
    6823, 6827, 6829, 6833, 6841, 6857, 6863, 6869, 6871, 6883, 6899,
    6907, 6911, 6917, 6947, 6949, 6959, 6961, 6967, 6971, 6977, 6983,
    6991, 6997, 7001, 7013, 7019, 7027, 7039, 7043, 7057, 7069, 7079,
    7103, 7109, 7121, 7127, 7129, 7151, 7159, 7177, 7187, 7193, 7207,
    7211, 7213, 7219, 7229, 7237, 7243, 7247, 7253, 7283, 7297, 7307,
    7309, 7321, 7331, 7333, 7349, 7351, 7369, 7393, 7411, 7417, 7433,
    7451, 7457, 7459, 7477, 7481, 7487, 7489, 7499, 7507, 7517, 7523,
    7529, 7537, 7541, 7547, 7549, 7559, 7561, 7573, 7577, 7583, 7589,
    7591, 7603, 7607, 7621, 7639, 7643, 7649, 7669, 7673, 7681, 7687,
    7691, 7699, 7703, 7717, 7723, 7727, 7741, 7753, 7757, 7759, 7789,
    7793, 7817, 7823, 7829, 7841, 7853, 7867, 7873, 7877, 7879, 7883,
    7901, 7907, 7919};
int pidx = 0;

/* a crude check for primeness */
int is_prime( long long n ) {
    int i;

    while( small_p[pidx]*small_p[pidx] < n ) {
        pidx++;
    }

    for( i = 0; i <= pidx; i++ ) {
        if( n == small_p[i] ) return 1;
	if( n % small_p[i] == 0 ) return 0;
    }

    return 1;
}

int main( int argc, char **argv ) {
    char *flag = malloc(TRY_MAX*sizeof(char));
    int count;

    int statcounter = 0;

    long int start=2;
    long int inc=1;
    long long int i, k, n, r1, r2, r3, r4;

    for( i = 0; i < TRY_MAX; i++ ) flag[i] = 1;

    if( flag == NULL ) {
	fprintf( stderr, "Couldn't allocate flag[] array.\n" );
	return 1;
    }

    /* if increment is given use it */
    if( argc > 2 ) {
        fprintf( stderr, "arg2: %s\n" , argv[2] );
	inc = strtol( argv[2], NULL, 10 );
    }

    /* if start is given use it */
    if( argc > 1 ) {
        fprintf( stderr, "arg1: %s\n" , argv[1] );
	start = strtol( argv[1], NULL, 10 );
    }

    fprintf( stderr, "start: %ld  inc: %ld\n", start, inc );


    for( n = start; n < TRY_MAX; n += inc ) {
	if( ! is_prime( n )) continue;

	/* In case we need to restart print status lines */
        if( statcounter++ > 100 ) {
	    fprintf( stderr, "%lld\n", n );
	    statcounter = 0;
	}

	/* We'll count down when we mark off different hits */
	count = n;

	/* Reset all of the hits to zero */
	for( i = 0; i < n; i++ ) flag[i]=1;

	/* one sanity check, just to make sure */
	if( (3*n+3)*n+1 < 0 ) {
	    fprintf( stderr, "negative self-test! n=%lld\n", n );
	    exit( 1 );
	}

	int fourk = (int)4*n;
	for( k = n-1; k >= 0; k-- ) {
            fourk -= 4;

	    /* calculate the 4 polynomials */
	    r1 = ( 3*k*k ) % n;
	    r2 = ( r1 + k ) % n;
	    r3 = ( r2 + k )  % n;
	    r4 = ( r3 + k + 1 ) % n;

	    /* check each result against our list */
	    if( flag[r1] ) {
		flag[r1] = 0;
		count--;
	    }

	    if( flag[r2] ) {
		flag[r2] = 0;
		count--;
	    }

	    if( flag[r3] ) {
		flag[r3] = 0;
		count--;
	    }

	    if( flag[r4] ) {
		flag[r4] = 0;
		count--;
	    }

            /* if there are too many left we can quit early */
	    if( count > fourk ) {
		/* fprintf( stderr, "break early\n" ); */
		break;
	    }
	}

	if( !count ) {
	    fprintf( stdout, "%lld\n", n );
	    fflush( stdout );
	}
    }

    exit( 0 );
}