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A088254 Primes p with property that if p = prime(k), if the product of all composite numbers between prime(k) and prime(k+1) is one less than a prime. 1

%I

%S 2,3,5,11,13,17,19,29,37,41,43,53,59,71,73,97,101,107,109,127,137,149,

%T 167,179,191,193,197,227,233,239,269,281,311,331,347,349,419,431,439,

%U 461,463,467,509,521,569,599,617,641,647,659,739,757,769,809,821,827

%N Primes p with property that if p = prime(k), if the product of all composite numbers between prime(k) and prime(k+1) is one less than a prime.

%C Conjecture: the sequence is infinite. The smaller member of the twin prime pairs is a term.

%H Harvey P. Dale, <a href="/A088254/b088254.txt">Table of n, a(n) for n = 1..1000</a>

%e 19 is a member as 20*21*22 +1 = 9241 is a prime.

%t Transpose[Select[Partition[Prime[Range[200]],2,1],PrimeQ[Times@@ Range[ First[#]+1, Last[#]-1]+1]&]][[1]] (* _Harvey P. Dale_, Oct 31 2011 *)

%K base,nonn

%O 1,1

%A _Amarnath Murthy_, Sep 27 2003

%E More terms from _David Wasserman_, Jul 25 2005

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Last modified July 18 07:10 EDT 2019. Contains 325134 sequences. (Running on oeis4.)