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A053778 First of four consecutive primes that comprise two sets of twin primes. +0
4
5, 11, 101, 137, 179, 191, 419, 809, 821, 1019, 1049, 1481, 1871, 1931, 2081, 2111, 2969, 3251, 3359, 3371, 3461, 4217, 4229, 4259, 5009, 5651, 5867, 6689, 6761, 6779, 6947, 7331, 7547, 8219, 8969, 9419, 9431, 9437, 10007, 11057, 11159, 11699, 12239 (list; graph; listen)
OFFSET

1,1

COMMENT

These twins are not necessarily at the minimal distance as in A007530 (which is a subsequence).

LINKS

M. F. Hasler, Table of n, a(n) for n=1,...,5274.

Eric Weisstein's World of Mathematics, Prime Quadruplet

FORMULA

A001359 primes for which A048614 is zero. Lesser of 2-twin primes after which the consecutive prime difference pattern (of A001223) is [2, 6k-2, 2] for some k.

EXAMPLE

These primes initiate consecutive p quadruples as follows: [p,p+2,p+6k,p+6k+2]. For 6k=6,12,18,24,30,36,54 such a p =5,137,1931,9437,2968, 20441 and 48677 resp. Such a quadruple is [48677,48679,48731,48733], with [2,52,2] difference pattern.

PROGRAM

(PARI) forprime( p=1, 10^5, isprime(p+2)|next; isprime(nextprime(p+4)+2) & print1(p", "))

(PARI) nextA053778(p)={until( isprime(nextprime(p+1)+2), until( p+2==p=nextprime(p+1), )); p-2}

(PARI) p=0; A053778=vector(100, i, p=nextA053778(p+1))

CROSSREFS

Cf. A001223, A001359, A007530, A048614.

Sequence in context: A120778 A042761 A123025 this_sequence A030079 A066596 A096473

Adjacent sequences: A053775 A053776 A053777 this_sequence A053779 A053780 A053781

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Mar 24 2000

EXTENSIONS

Edited by N. J. A. Sloane (njas(AT)research.att.com), Apr 13 2008, at the suggestion of M. F. Hasler.

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Last modified December 16 17:18 EST 2009. Contains 170825 sequences.


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