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%I #29 Jul 03 2020 12:04:58
%S 347,1427,2687,4931,13901,21557,23741,27941,28277,31247,32057,33617,
%T 45821,55661,55817,68207,68897,91571,128657,128981,167621,179897,
%U 193871,205421,221717,234191,239231,258107,258611,259157,278807,302831,305477,348431,354371
%N Initial primes of 5 consecutive primes with consecutive gaps 2, 4, 6, 8.
%C All terms = {11,17} mod 30.
%C a(n) + 20 is the greatest term in the sequence of 5 consecutive primes with 4 consecutive gaps 2, 4, 6, 8. - _Muniru A Asiru_, Aug 03 2017
%H Zak Seidov, <a href="/A190814/b190814.txt">Table of n, a(n) for n = 1..2000</a>
%e Prime(69..73) = {347, 349, 353, 359, 367} and 349 - 347 = 2, 353 - 349 = 4, 359 - 353 = 6, 367 - 359 = 8.
%p N:= 10^6: # to get all terms <= N
%p Primes:= select(isprime, [seq(i,i=3..N+20,2)]):
%p Primes[select(t -> [Primes[t+1]-Primes[t],Primes[t+2]-Primes[t+1],Primes[t+3]-Primes[t+2],Primes[t+4]-Primes[t+3]] = [2,4,6,8], [$1..nops(Primes)-4])]; # _Robert Israel_, Aug 03 2017
%t d = Differences[Prime[Range[100000]]]; Prime[Flatten[Position[Partition[d, 4, 1], {2, 4, 6, 8}]]] (* _T. D. Noe_, May 23 2011 *)
%t Select[Partition[Prime[Range[31000]],5,1],Differences[#]=={2,4,6,8}&][[All,1]] (* _Harvey P. Dale_, Jul 03 2020 *)
%Y Subsequence of A190799, also subsequence of A078847.
%Y Cf. A190792, A190817, A190819, A190838.
%K nonn
%O 1,1
%A _Zak Seidov_, May 20 2011
%E Additional cross references from _Harvey P. Dale_, May 10 2014
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