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A190814 Initial primes of 5 consecutive primes with consecutive gaps 2, 4, 6, 8. 11
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 (list; graph; refs; listen; history; text; internal format)
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

LINKS

Zak Seidov, Table of n, a(n) for n = 1..2000

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.

Cf. A190792, A190817, A190819, A190838.

Sequence in context: A210363 A054823 A142369 * A012868 A226669 A226665

Adjacent sequences:  A190811 A190812 A190813 * A190815 A190816 A190817

KEYWORD

nonn

AUTHOR

Zak Seidov, May 20 2011

EXTENSIONS

Additional cross references from Harvey P. Dale, May 10 2014

STATUS

approved

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Last modified January 24 18:07 EST 2021. Contains 340411 sequences. (Running on oeis4.)