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A103807 Primes p such that 2*p-27, 2*p+27, 2*p-33 and 2*p+33 are primes or -1 times primes. 0

%I

%S 2,5,7,23,37,103,313,457,733,863,2053,2063,2917,4723,7187,7817,8017,

%T 9007,9473,9973,10687,11527,11923,13477,13883,15787,26833,31477,34897,

%U 36097,36353,36493,39937,44417,46447,47623,52103,53377,55813,60737

%N Primes p such that 2*p-27, 2*p+27, 2*p-33 and 2*p+33 are primes or -1 times primes.

%C Intersection of A103805 and A103806.

%t Intersection[Select[Range[100000], PrimeQ[ # ]&&PrimeQ[2#+33]&&PrimeQ[2#-33]&&PrimeQ[ # ]&&PrimeQ[2#+27]&&PrimeQ[2#-27]&]]

%t okQ[n_]:=Module[{x=2n},And@@PrimeQ[{x-27,x+27,x-33,x+33}]]; Select[Prime[Range[7000]],okQ] (* _Harvey P. Dale_, Jan 23 2011 *)

%o (MAGMA) [ p: p in PrimesUpTo(61000) | IsPrime(2*p-27) and IsPrime(2*p+27) and IsPrime(2*p-33) and IsPrime(2*p+33) ];

%o (PARI) {forprime(p=2, 61000, if(isprime(abs(2*p-27))&&isprime(2*p+27)&&isprime(abs(2*p-33))&&isprime(2*p+33), print1(p, ", ")))}

%Y Cf. A103805, A103806.

%K nonn

%O 1,1

%A _Zak Seidov_, Feb 16 2005

%E Definition clarified, comment adjusted, MAGMA and PARI programs added by _Klaus Brockhaus_, Mar 21 2010

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Last modified April 15 01:24 EDT 2021. Contains 342974 sequences. (Running on oeis4.)