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A190814
Initial primes of 5 consecutive primes with consecutive gaps 2, 4, 6, 8.
12
347, 1427, 2687, 4931, 13901, 21557, 23741, 27941, 28277, 31247, 32057, 33617, 45821, 55661, 55817, 68207, 68897, 91571, 128657, 128981, 167621, 179897, 193871, 205421, 221717, 234191, 239231, 258107, 258611, 259157, 278807, 302831, 305477, 348431, 354371
OFFSET
1,1
COMMENTS
All terms = {11,17} mod 30.
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
EXAMPLE
Prime(69..73) = {347, 349, 353, 359, 367} and 349 - 347 = 2, 353 - 349 = 4, 359 - 353 = 6, 367 - 359 = 8.
MAPLE
N:= 10^6: # to get all terms <= N
Primes:= select(isprime, [seq(i, i=3..N+20, 2)]):
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
MATHEMATICA
d = Differences[Prime[Range[100000]]]; Prime[Flatten[Position[Partition[d, 4, 1], {2, 4, 6, 8}]]] (* T. D. Noe, May 23 2011 *)
Select[Partition[Prime[Range[31000]], 5, 1], Differences[#]=={2, 4, 6, 8}&][[All, 1]] (* Harvey P. Dale, Jul 03 2020 *)
CROSSREFS
Subsequence of A190799, also subsequence of A078847.
Sequence in context: A054823 A343701 A142369 * A012868 A343303 A226669
KEYWORD
nonn
AUTHOR
Zak Seidov, May 20 2011
EXTENSIONS
Additional cross references from Harvey P. Dale, May 10 2014
STATUS
approved