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A216150
Smallest prime q such that sum(i=1..n-1, q mod(prime(i))) == q mod prime(n).
0
7, 2, 11, 71, 331, 13, 4217, 4643, 16381, 6007, 225217, 260339, 4772483, 117351431, 130554581, 2499413753
OFFSET
2,1
COMMENTS
The sequence is infinite.
EXAMPLE
n = 2: p_n = 3, q = 7,7 (mod 2) = 1 and 1 = 7 (mod 3);
n = 3: p_n = 5, q = 2, 2 (mod(2,3)) = (0,2) and 0 + 2 = 2 = 2 (mod 5);
n = 4: p_n = 7, q = 11, 11 (mod(2,3,5)) = (1,2,1) and 1 + 2 + 1 = 4 = 11 (mod 7);
n = 5: p_n = 11, q = 71, 71 (mod(2,3,5,7)) = (1,2,1,1) and 1 + 2 + 1 + 1 = 5 = 71 (mod 11).
PROG
(PARI) for(n=2, 50, p=prime(n); q=2; while(sum(i=1, n-1, q%prime(i))<>q%p, q=nextprime(q+1)); print(n", "q))
CROSSREFS
Sequence in context: A248283 A147677 A090243 * A145338 A104586 A323995
KEYWORD
nonn,more,hard
AUTHOR
Zak Seidov, Sep 02 2012
STATUS
approved