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%I #10 Sep 10 2014 12:25:10
%S 907,1307,1439,1459,1669,1879,2089,2141,2351,2713,4139,4759,4969,5179,
%T 5417,6047,6101,6353,6779,6793,7919,8369,8663,9049,9349,9491,9533,
%U 9623,9769,10099,10691,10883,11083,11213,11369,11399,11621,11789,11887,11923,12097,12119
%N Primes p with property that there exists a number d>0 such that numbers p-k*d, k=1...6, are six primes.
%C Conjecture: only 312722 primes are not in the sequence: 2, 3, ..., 198702899.
%e 907 is in the sequence because with d = 150: 7, 157, 307, 457, 607, 757 are all primes.
%t fQ[p_] := Module[{d = 1}, While[6*d < p && Union[PrimeQ[p - Range[6]*d]] != {True}, d++]; 6*d < p]; Select[Prime[Range[4, PrimePi[12119]]], fQ] (* _T. D. Noe_, Sep 07 2012 *)
%o (PARI) is(n)=my(t); forprime(p=2,n-20,if((n-p)%6==0 && isprime((t=(n-p)/6)+p) && isprime(2*t+p) && isprime(3*t+p) && isprime(4*t+p) && isprime(5*t+p) && isprime(n), return(1))); 0 \\ _Charles R Greathouse IV_, Sep 10 2014
%Y Cf. A215895, A216495, A094383, A216497, A216498.
%K nonn
%O 1,1
%A _Alex Ratushnyak_, Sep 07 2012
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