%I A119912
%S A119912 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,
%T A119912 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,
%U A119912 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
%N A119912 Scan A076368, discard any nonprimes.
%C A119912 Primes that are one greater than the difference between consecutive primes.
%H A119912 Cino Hilliard, <a href="http://groups.msn.com/First300billionprimes/primecounts.msnw">
Frequency of primes</a>.
%e A119912 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.
%p A119912 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(w-k+1) then print(w-k+1); fi; od; end:
P(10000);
%o A119912 (PARI) diffp1p2(n) = { local(p1,p2,y); for(x=1,n, p1=prime(x); p2=prime(x+1);
y=(p2-p1)+1; if(isprime(y), print1(y",") ) ) } - Cino Hilliard (hillcino368(AT)hotmail.com),
May 23 2007
%Y A119912 Cf. A076368.
%Y A119912 Sequence in context: A069461 A063256 A131320 this_sequence A076368 A071049
A140187
%Y A119912 Adjacent sequences: A119909 A119910 A119911 this_sequence A119913 A119914
A119915
%K A119912 easy,nonn
%O A119912 0,1
%A A119912 Paolo P. Lava & Giorgio Balzarotti (ppl(AT)spl.at), Aug 02 2006
%E A119912 Edited by N. J. A. Sloane (njas(AT)research.att.com), Jul 02 2008 at
the suggestion of R. J. Mathar
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