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A022010 Initial members of prime septuplets (p, p+2, p+8, p+12, p+14, p+18, p+20). 33

%I

%S 5639,88799,284729,626609,855719,1146779,6560999,7540439,8573429,

%T 17843459,19089599,24001709,42981929,43534019,69156539,74266259,

%U 79208399,80427029,84104549,87988709,124066079,128469149,144214319,157131419,208729049,218033729

%N Initial members of prime septuplets (p, p+2, p+8, p+12, p+14, p+18, p+20).

%C All terms are congruent to 179 (modulo 210). - _Matt C. Anderson_, May 26 2015

%H Matt C. Anderson and Dana Jacobsen, <a href="/A022010/b022010.txt">Table of n, a(n) for n = 1..10000</a> [first 1000 terms from Matt C. Anderson]

%H T. Forbes, <a href="http://anthony.d.forbes.googlepages.com/ktuplets.htm">Prime k-tuplets</a>

%t Select[Prime[Range[2 10^8]], Union[PrimeQ[# + {2, 8, 12, 14, 18, 20}]] == {True} &] (* _Vincenzo Librandi_, Oct 01 2015 *)

%t Select[Partition[Prime[Range[12021000]],7,1],Differences[#]=={2,6,4,2,4,2}&][[All,1]] (* or *) Select[Range[179,219*10^6,210], AllTrue[ #+{0,2,8,12,14,18,20},PrimeQ]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jun 04 2019 *)

%o (Perl) use ntheory ":all"; say for sieve_prime_cluster(1,1e9, 2,8,12,14,18,20); # _Dana Jacobsen_, Sep 30 2015

%o (MAGMA) [p: p in PrimesUpTo(3*10^8) | forall{p+r: r in [2, 8, 12, 14, 18, 20] | IsPrime(p+r)}]; // _Vincenzo Librandi_, Oct 01 2015

%o (PARI) forprime(p=2, 10^30, if (isprime(p+2) && isprime(p+8) && isprime(p+12) && isprime(p+14) && isprime(p+18) && isprime(p+20), print1(p", "))) \\ _Altug Alkan_, Oct 01 2015

%K nonn

%O 1,1

%A _Warut Roonguthai_

%E More terms from a Maple program by _Matt C. Anderson_, Dec 05 2013

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Last modified February 24 22:04 EST 2020. Contains 332216 sequences. (Running on oeis4.)