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Starting from P0=3, the sequence list the minimum prime P1>P0 for which the expression P=P1+P0-1 is also a prime. The search then restarts from P1.
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%I #10 Nov 21 2013 12:49:02

%S 3,5,7,11,13,17,31,37,43,47,61,67,71,79,89,103,109,131,139,173,181,

%T 193,197,223,227,241,251,271,277,281,283,311,331,347,373,379,383,439,

%U 443,487,491,523,541,547,557,607,617,643,647,661,701,709,719,733,739,743

%N Starting from P0=3, the sequence list the minimum prime P1>P0 for which the expression P=P1+P0-1 is also a prime. The search then restarts from P1.

%H Harvey P. Dale, <a href="/A126145/b126145.txt">Table of n, a(n) for n = 0..1000</a>

%e 3+5-1=7 is a prime. 5 is in the sequence.

%e 5+7-1=11 is a prime: 11 is in the sequence.

%e 11+13-1=23 is a prime: 13 is in the sequence.

%e 13+17-1=29 is a prime: 17 is in the sequence.

%e 17+19-1=35 is not a prime.

%p P:=proc(n) local i,w; w:=3; for i from 3 by 1 to n do if isprime(w+ithprime(i)-1) then print(ithprime(i)); w:=ithprime(i); fi; od; end: P(500);

%t nxt[n_]:=NestWhile[NextPrime[#]&,NextPrime[n],!PrimeQ[n+#-1]&]; NestList[ nxt, 3,60] (* _Harvey P. Dale_, Oct 02 2011 *)

%K easy,nonn

%O 0,1

%A _Paolo P. Lava_ and _Giorgio Balzarotti_, Mar 07 2007, Mar 08 2007