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 A275475 Primes p such that p+2^3, p+2^5 and p+2^7 are all primes. 1

%I

%S 11,29,71,149,491,599,701,1439,1451,2339,3761,4211,5399,5651,6269,

%T 6701,7541,9059,9311,9689,9941,10859,11831,12569,12791,13679,15299,

%U 15551,16979,18089,19301,19469,22031,22541,23549,23879,25229,25841,27329,27791,28541,30809

%N Primes p such that p+2^3, p+2^5 and p+2^7 are all primes.

%H Dana Jacobsen, <a href="/A275475/b275475.txt">Table of n, a(n) for n = 1..10000</a>

%e 11 is in the sequence because 11+8 = 19, 11+32 = 43 and 11+128 = 139 are all primes.

%e 29 is in the sequence because 29+8 = 37, 29+32 = 61 and 29+128 = 157 are all primes.

%t Select[Prime@ Range@ 3450, Function[k, Times @@ Boole@ PrimeQ@ Map[k + 2^# &, {3, 5, 7}] == 1]] (* _Michael De Vlieger_, Aug 10 2016 *)

%t Select[Prime[Range[4000]],AllTrue[#+{8,32,128},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Apr 26 2018 *)

%o (Perl) use ntheory ":all"; say for sieve_prime_cluster(2, 1e6, 2**3, 2**5, 2**7); # _Dana Jacobsen_, Sep 29 2016

%Y Cf. A269257, A269258, A269259, A269859, A270203.

%Y Cf. A275485 (a subsequence).

%K nonn

%O 1,1

%A _Debapriyay Mukhopadhyay_, Jul 29 2016

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Last modified May 22 00:25 EDT 2019. Contains 323472 sequences. (Running on oeis4.)