

A119912


Scan A076368, discard any nonprimes.


1



2, 3, 3, 5, 3, 5, 3, 5, 7, 3, 7, 5, 3, 5, 7, 7, 3, 7, 5, 3, 7, 5, 7, 5, 3, 5, 3, 5, 5, 7, 3, 11, 3, 7, 7, 5, 7, 7, 3, 11, 3, 5, 3, 13, 13, 5, 3, 5, 7, 3, 11, 7, 7, 7, 3, 7, 5, 3, 11, 5, 3, 5, 7, 11, 3, 5, 7, 7, 7, 5, 7, 5, 11, 3, 11, 3, 7, 5, 7, 5, 3, 5, 13, 5, 5, 7, 13, 3, 19, 7, 11, 7, 7, 3, 7, 11, 7, 7, 3
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OFFSET

0,1


COMMENTS

Primes that are one greater than the difference between consecutive primes.


LINKS

Table of n, a(n) for n=0..98.
Cino Hilliard, Frequency of primes.


EXAMPLE

The first 4 consecutive prime pairs are (2,3),(3,5),(5,7),(7,11). The differences + 1 are the primes 2,3,3,5, the first four entries in the sequence.


MAPLE

P:=proc(n) local cont, i, j, k, w; for i from 1 by 1 to n do k:=ithprime(i); w:=ithprime(i+1); if isprime(wk+1) then print(wk+1); fi; od; end: P(10000);


MATHEMATICA

Select[Differences[Prime[Range[200]]]+1, PrimeQ] (* Harvey P. Dale, Jul 02 2017 *)


PROG

(PARI) diffp1p2(n) = { local(p1, p2, y); for(x=1, n, p1=prime(x); p2=prime(x+1); y=(p2p1)+1; if(isprime(y), print1(y", ") ) ) }  Cino Hilliard, May 23 2007


CROSSREFS

Cf. A076368.
Sequence in context: A229703 A131320 A020483 * A076368 A279931 A071049
Adjacent sequences: A119909 A119910 A119911 * A119913 A119914 A119915


KEYWORD

easy,nonn


AUTHOR

Paolo P. Lava and Giorgio Balzarotti, Aug 02 2006


EXTENSIONS

Edited by N. J. A. Sloane, Jul 02 2008 at the suggestion of R. J. Mathar


STATUS

approved



