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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
2, 5, 7, 23, 37, 103, 313, 457, 733, 863, 2053, 2063, 2917, 4723, 7187, 7817, 8017, 9007, 9473, 9973, 10687, 11527, 11923, 13477, 13883, 15787, 26833, 31477, 34897, 36097, 36353, 36493, 39937, 44417, 46447, 47623, 52103, 53377, 55813, 60737 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A103805 and A103806.

LINKS

Table of n, a(n) for n=1..40.

MATHEMATICA

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

okQ[n_]:=Module[{x=2n}, And@@PrimeQ[{x-27, x+27, x-33, x+33}]]; Select[Prime[Range[7000]], okQ]  [From Harvey P. Dale, Jan. 23, 2011]

PROG

(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) ];

(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, ", ")))}

CROSSREFS

Cf. A103805, A103806.

Sequence in context: A103060 A256247 A243595 * A099228 A182474 A106018

Adjacent sequences:  A103804 A103805 A103806 * A103808 A103809 A103810

KEYWORD

nonn

AUTHOR

Zak Seidov, Feb 16 2005

EXTENSIONS

Definition clarified, comment adjusted, MAGMA and PARI program added by Klaus Brockhaus, Mar 21 2010

STATUS

approved

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Last modified November 21 12:51 EST 2017. Contains 295001 sequences.