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A190583 The smallest prime(j) in a sequence of 7 consecutive primes such that the associated 2*prime(k)+3, k=j..j+6, are also prime. 0
4827859, 5413813, 59069473, 59069489, 171426679, 189784123, 191766193, 196232137, 306928507, 359727833, 367733497, 409634959, 452273897, 508068287, 644033227, 665209213, 737454929, 879260659, 889580717, 924491669 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Concerning the even more stringent case of 8 consecutive primes: 59069473 is the least prime(j) of 8 consecutives primes prime(k) such that 2*prime(k)+3 are primes for k=j to j+7 and 3203934593 is the next prime with the same property.

LINKS

Table of n, a(n) for n=1..20.

EXAMPLE

4827859, 4827863, ..., 4827943 are seven consecutive primes, and the associated seven 9655721, 9655729, ..., 9655889 are also prime numbers. This puts 4827859 into the sequence.

MAPLE

isA023204 := proc(n) isprime(n) and isprime(2*n+3) ; end proc:

isA190583 := proc(n) local q, s ; q := n ; if isA023204(q) then for s from 1 to 6 do q := nextprime(q) ; if not isA023204(q) then return false; end if; end do; return true; else return false; end if; end proc:

p := 2 : for i from 1 do if isA190583(p) then print(p) ; end if; p := nextprime(p) ; end do: # R. J. Mathar, Jun 02 2011

CROSSREFS

Cf. A190478.

Sequence in context: A248587 A204053 A017538 * A034637 A043637 A232676

Adjacent sequences:  A190580 A190581 A190582 * A190584 A190585 A190586

KEYWORD

nonn

AUTHOR

Pierre CAMI, May 13 2011

STATUS

approved

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Last modified July 6 02:23 EDT 2022. Contains 355108 sequences. (Running on oeis4.)